To my big surprise, it worked with Kubuntu 12.04 So it is a clear regression, most probably caused by adding QMI&MBIM support to the kernel and to the ModemManager, also by ModemManager relying on newer QMI versions than those provided by older modems, and by absence of testing ModemManager on this hardware, old now but once quite popular in its times. In Kubuntu Precise it works using just usb/option driver, without qmi/mbim packages : ii linux-image-3.2.0-95-generic 3.2.0-95.135 Linux kernel image for version 3.2.0 on 64 bit x86 SMP ii modemmanager 0.5.2.0-0ubuntu2 D-Bus service for managing modems ii network-manager 0.9.4.0-0ubuntu4.4.1 network management framework (daemon and userspace tools) logs: Dec 13 11:39:13 ubuntu kernel: [ 411.764690] usb 2-1.1: new high-speed USB device number 4 using ehci_hcd Dec 13 11:39:13 ubuntu kernel: [ 411.857680] hub 2-1.1:1.0: USB hub found Dec 13 11:39:13 ubuntu kernel: [ 411.861050] hub 2-1.1:1.0: 4 ports detected Dec 13 11:39:15 ubuntu kernel: [ 414.094366] hub 2-1.1:1.0: unable to enumerate USB device on port 2 Dec 13 11:39:16 ubuntu kernel: [ 414.645213] usb 2-1.1.2: new full-speed USB device number 6 using ehci_hcd Dec 13 11:39:16 ubuntu mtp-probe: checking bus 2, device 6: "/sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.1/2-1.1.2" Dec 13 11:39:16 ubuntu kernel: [ 414.742807] scsi5 : usb-storage 2-1.1.2:1.4 Dec 13 11:39:16 ubuntu mtp-probe: bus: 2, device: 6 was not an MTP device Dec 13 11:39:16 ubuntu kernel: [ 415.190358] usbcore: registered new interface driver usbserial Dec 13 11:39:16 ubuntu kernel: [ 415.190386] USB Serial support registered for generic Dec 13 11:39:16 ubuntu kernel: [ 415.190489] usbcore: registered new interface driver usbserial_generic Dec 13 11:39:16 ubuntu kernel: [ 415.190493] usbserial: USB Serial Driver core Dec 13 11:39:16 ubuntu kernel: [ 415.199770] USB Serial support registered for GSM modem (1-port) Dec 13 11:39:16 ubuntu kernel: [ 415.200560] option 2-1.1.2:1.1: GSM modem (1-port) converter detected Dec 13 11:39:16 ubuntu kernel: [ 415.200764] usb 2-1.1.2: GSM modem (1-port) converter now attached to ttyUSB0 Dec 13 11:39:16 ubuntu kernel: [ 415.200839] option 2-1.1.2:1.2: GSM modem (1-port) converter detected Dec 13 11:39:16 ubuntu kernel: [ 415.201051] usb 2-1.1.2: GSM modem (1-port) converter now attached to ttyUSB1 Dec 13 11:39:16 ubuntu kernel: [ 415.201126] option 2-1.1.2:1.3: GSM modem (1-port) converter detected Dec 13 11:39:16 ubuntu kernel: [ 415.201330] usb 2-1.1.2: GSM modem (1-port) converter now attached to ttyUSB2 Dec 13 11:39:16 ubuntu kernel: [ 415.201373] usbcore: registered new interface driver option Dec 13 11:39:16 ubuntu kernel: [ 415.201377] option: v0.7.2:USB Driver for GSM modems Dec 13 11:39:16 ubuntu modem-manager[1060]: (ttyUSB1) opening serial port... Dec 13 11:39:16 ubuntu modem-manager[1060]: (ttyUSB0) opening serial port... Dec 13 11:39:16 ubuntu modem-manager[1060]: (ttyUSB2) opening serial port... Dec 13 11:39:17 ubuntu kernel: [ 415.741615] scsi 5:0:0:0: CD-ROM CMOTECH Mass Storage 2.31 PQ: 0 ANSI: 6 Dec 13 11:39:17 ubuntu kernel: [ 415.775562] sr0: scsi3-mmc drive: 0x/0x caddy Dec 13 11:39:17 ubuntu kernel: [ 415.775569] cdrom: Uniform CD-ROM driver Revision: 3.20 Dec 13 11:39:17 ubuntu kernel: [ 415.776461] sr 5:0:0:0: Attached scsi CD-ROM sr0 Dec 13 11:39:17 ubuntu kernel: [ 415.776807] sr 5:0:0:0: Attached scsi generic sg2 type 5 Dec 13 11:39:17 ubuntu kernel: [ 415.875299] sr0: CDROM (ioctl) error, command: Xpwrite, Read disk info 51 00 00 00 00 00 00 00 02 00 Dec 13 11:39:17 ubuntu kernel: [ 415.875321] sr: Sense Key : Hardware Error [current] Dec 13 11:39:17 ubuntu kernel: [ 415.875329] sr: Add. Sense: No additional sense information Dec 13 11:39:17 ubuntu ata_id[2501]: HDIO_GET_IDENTITY failed for '/dev/sr0': Invalid argument Dec 13 11:39:17 ubuntu modem-manager[1060]: (ttyUSB0) closing serial port... Dec 13 11:39:17 ubuntu modem-manager[1060]: (ttyUSB0) serial port closed Dec 13 11:39:17 ubuntu modem-manager[1060]: (ttyUSB0) opening serial port... Dec 13 11:39:17 ubuntu modem-manager[1060]: (Generic): CDMA modem /sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.1/2-1.1.2 claimed port ttyUSB0 Dec 13 11:39:17 ubuntu modem-manager[1060]: (ttyUSB0) closing serial port... Dec 13 11:39:17 ubuntu modem-manager[1060]: (ttyUSB0) serial port closed Dec 13 11:39:29 ubuntu modem-manager[1060]: (ttyUSB1) closing serial port... Dec 13 11:39:29 ubuntu modem-manager[1060]: (ttyUSB1) serial port closed Dec 13 11:39:29 ubuntu modem-manager[1060]: (ttyUSB1) opening serial port... Dec 13 11:39:29 ubuntu modem-manager[1060]: (ttyUSB2) closing serial port... Dec 13 11:39:29 ubuntu modem-manager[1060]: (ttyUSB2) serial port closed Dec 13 11:39:29 ubuntu modem-manager[1060]: (ttyUSB2) opening serial port... Dec 13 11:39:32 ubuntu modem-manager[1060]: (ttyUSB1) closing serial port... Dec 13 11:39:32 ubuntu modem-manager[1060]: (ttyUSB1) serial port closed Dec 13 11:39:32 ubuntu modem-manager[1060]: (Generic): CDMA modem /sys/devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.1/2-1.1.2 claimed port ttyUSB1 Dec 13 11:39:35 ubuntu modem-manager[1060]: (ttyUSB2) closing serial port... Dec 13 11:39:35 ubuntu modem-manager[1060]: (ttyUSB2) serial port closed Dec 13 11:39:35 ubuntu NetworkManager[1086]: (ttyUSB0): failed to look up interface index Dec 13 11:39:35 ubuntu NetworkManager[1086]: (ttyUSB0): new CDMA/EVDO device (driver: 'option1' ifindex: 0) Dec 13 11:39:35 ubuntu NetworkManager[1086]: (ttyUSB0): exported as /org/freedesktop/NetworkManager/Devices/2 Dec 13 11:39:35 ubuntu NetworkManager[1086]: (ttyUSB0): now managed Dec 13 11:39:35 ubuntu NetworkManager[1086]: (ttyUSB0): device state change: unmanaged -> unavailable (reason 'managed') [10 20 2] Dec 13 11:39:35 ubuntu NetworkManager[1086]: (ttyUSB0): deactivating device (reason 'managed') [2] Dec 13 11:39:35 ubuntu NetworkManager[1086]: nm_system_iface_flush_routes: assertion `ifindex > 0' failed Dec 13 11:39:35 ubuntu NetworkManager[1086]: nm_system_iface_flush_addresses: assertion `ifindex > 0' failed Dec 13 11:39:35 ubuntu NetworkManager[1086]: (ttyUSB0): device state change: unavailable -> disconnected (reason 'none') [20 30 0] Dec 13 11:39:41 ubuntu ata_id[2563]: HDIO_GET_IDENTITY failed for '/dev/sr0': Invalid argument Dec 13 11:41:43 ubuntu modem-manager[1060]: (ttyUSB0) opening serial port... Dec 13 11:41:43 ubuntu modem-manager[1060]: Modem /org/freedesktop/ModemManager/Modems/0: state changed (disabled -> enabling) Dec 13 11:41:43 ubuntu modem-manager[1060]: (ttyUSB1) opening serial port... Dec 13 11:41:43 ubuntu modem-manager[1060]: Modem /org/freedesktop/ModemManager/Modems/0: state changed (enabling -> enabled) Dec 13 11:41:43 ubuntu NetworkManager[1086]: WWAN now enabled by management service Dec 13 11:41:43 ubuntu modem-manager[1060]: Modem /org/freedesktop/ModemManager/Modems/0: state changed (enabled -> registered) Dec 13 11:43:22 ubuntu NetworkManager[1086]: keyfile: updating /etc/NetworkManager/system-connections/InterTelecom Dec 13 11:43:27 ubuntu NetworkManager[1086]: keyfile: updating /etc/NetworkManager/system-connections/InterTelecom Dec 13 11:44:46 ubuntu NetworkManager[1086]: Activation (ttyUSB0) starting connection 'InterTelecom' Dec 13 11:44:46 ubuntu NetworkManager[1086]: (ttyUSB0): device state change: disconnected -> prepare (reason 'none') [30 40 0] Dec 13 11:44:46 ubuntu NetworkManager[1086]: Activation (ttyUSB0) Stage 1 of 5 (Device Prepare) scheduled... Dec 13 11:44:46 ubuntu NetworkManager[1086]: Activation (ttyUSB0) Stage 1 of 5 (Device Prepare) started... Dec 13 11:44:46 ubuntu NetworkManager[1086]: Activation (ttyUSB0) Stage 1 of 5 (Device Prepare) complete. Dec 13 11:44:46 ubuntu modem-manager[1060]: Modem /org/freedesktop/ModemManager/Modems/0: state changed (registered -> connecting) Dec 13 11:44:48 ubuntu modem-manager[1060]: Modem /org/freedesktop/ModemManager/Modems/0: state changed (connecting -> connected) Dec 13 11:44:48 ubuntu NetworkManager[1086]: Activation (ttyUSB0) Stage 2 of 5 (Device Configure) scheduled... Dec 13 11:44:48 ubuntu NetworkManager[1086]: Activation (ttyUSB0) Stage 2 of 5 (Device Configure) starting... Dec 13 11:44:48 ubuntu NetworkManager[1086]: (ttyUSB0): device state change: prepare -> config (reason 'none') [40 50 0] Dec 13 11:44:48 ubuntu NetworkManager[1086]: Activation (ttyUSB0) Stage 2 of 5 (Device Configure) successful. Dec 13 11:44:48 ubuntu NetworkManager[1086]: Activation (ttyUSB0) Stage 3 of 5 (IP Configure Start) scheduled. Dec 13 11:44:48 ubuntu NetworkManager[1086]: Activation (ttyUSB0) Stage 2 of 5 (Device Configure) complete. Dec 13 11:44:48 ubuntu NetworkManager[1086]: Activation (ttyUSB0) Stage 3 of 5 (IP Configure Start) started... Dec 13 11:44:48 ubuntu NetworkManager[1086]: (ttyUSB0): device state change: config -> ip-config (reason 'none') [50 70 0] Dec 13 11:44:48 ubuntu NetworkManager[1086]: starting PPP connection Dec 13 11:44:48 ubuntu NetworkManager[1086]: pppd started with pid 2903 Dec 13 11:44:48 ubuntu NetworkManager[1086]: Activation (ttyUSB0) Stage 4 of 5 (IPv6 Configure Timeout) scheduled... Dec 13 11:44:48 ubuntu NetworkManager[1086]: Activation (ttyUSB0) Stage 3 of 5 (IP Configure Start) complete. Dec 13 11:44:48 ubuntu NetworkManager[1086]: Activation (ttyUSB0) Stage 4 of 5 (IPv6 Configure Timeout) started... Dec 13 11:44:48 ubuntu NetworkManager[1086]: Activation (ttyUSB0) Stage 4 of 5 (IPv6 Configure Timeout) complete. Dec 13 11:44:48 ubuntu pppd[2903]: Plugin /usr/lib/pppd/2.4.5/nm-pppd-plugin.so loaded. Dec 13 11:44:48 ubuntu pppd[2903]: pppd 2.4.5 started by root, uid 0 Dec 13 11:44:48 ubuntu NetworkManager[1086]: SCPlugin-Ifupdown: devices added (path: /sys/devices/virtual/net/ppp0, iface: ppp0) Dec 13 11:44:48 ubuntu NetworkManager[1086]: SCPlugin-Ifupdown: device added (path: /sys/devices/virtual/net/ppp0, iface: ppp0): no ifupdown configuration found. Dec 13 11:44:48 ubuntu pppd[2903]: Using interface ppp0 Dec 13 11:44:48 ubuntu pppd[2903]: Connect: ppp0 <--> /dev/ttyUSB0 Dec 13 11:44:48 ubuntu pppd[2903]: PAP authentication succeeded Dec 13 11:44:50 ubuntu kernel: [ 748.595236] PPP BSD Compression module registered Dec 13 11:44:53 ubuntu kernel: [ 752.131756] PPP Deflate Compression module registered Dec 13 11:44:55 ubuntu pppd[2903]: local IP address 10.144.4.31 Dec 13 11:44:55 ubuntu pppd[2903]: remote IP address 78.111.176.141 Dec 13 11:44:55 ubuntu pppd[2903]: primary DNS address 192.168.4.46 Dec 13 11:44:55 ubuntu pppd[2903]: secondary DNS address 192.168.4.45 Dec 13 11:44:55 ubuntu NetworkManager[1086]: PPP manager(IP Config Get) reply received. Dec 13 11:44:55 ubuntu NetworkManager[1086]: Activation (ttyUSB0) Stage 5 of 5 (IPv4 Configure Commit) scheduled... Dec 13 11:44:55 ubuntu NetworkManager[1086]: Activation (ttyUSB0) Stage 5 of 5 (IPv4 Commit) started... Dec 13 11:44:56 ubuntu NetworkManager[1086]: (ppp0): writing resolv.conf to /sbin/resolvconf Dec 13 11:44:56 ubuntu dnsmasq[2215]: setting upstream servers from DBus Dec 13 11:44:56 ubuntu dnsmasq[2215]: using nameserver 192.168.4.45#53 Dec 13 11:44:56 ubuntu dnsmasq[2215]: using nameserver 192.168.4.46#53 Dec 13 11:44:56 ubuntu NetworkManager[1086]: (ttyUSB0): device state change: ip-config -> activated (reason 'none') [70 100 0] Dec 13 11:45:54 ubuntu NetworkManager[1086]: Policy set 'InterTelecom' (ppp0) as default for IPv4 routing and DNS. Dec 13 11:45:54 ubuntu NetworkManager[1086]: Activation (ttyUSB0) successful, device activated. Dec 13 11:45:54 ubuntu NetworkManager[1086]: Activation (ttyUSB0) Stage 5 of 5 (IPv4 Commit) complete. Dec 13 11:45:54 ubuntu dbus[1041]: [system] Activating service name='org.freedesktop.nm_dispatcher' (using servicehelper) Dec 13 11:45:54 ubuntu dbus[1041]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher'