"Use as hotspot" does not work in Ubuntu 14.10

Step to reproduce :
go to settings > Network
click on "Use as hotspot"

Expected result:
It displays the connexion information and the network can be seen by other devices.

Actual :
Connexion informations are displayed, but no wifi network seems to have been created.

I'm actually not sure network-manager is the right package, but in /var/log/syslog I have:

Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> (wlan0): disconnecting for new activation request.
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> (wlan0): device state change: config -> disconnected (reason 'none') [50 30 0]
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> (wlan0): deactivating device (reason 'none') [0]
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0) starting connection 'Hotspot'
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> (wlan0): device state change: disconnected -> prepare (reason 'none') [30 40 0]
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0) Stage 1 of 5 (Device Prepare) scheduled...
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0) Stage 1 of 5 (Device Prepare) started...
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0) Stage 2 of 5 (Device Configure) scheduled...
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0) Stage 1 of 5 (Device Prepare) complete.
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0) Stage 2 of 5 (Device Configure) starting...
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> (wlan0): device state change: prepare -> config (reason 'none') [40 50 0]
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0/wireless): access point 'Hotspot' has security, but secrets are required.
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> (wlan0): device state change: config -> need-auth (reason 'none') [50 60 0]
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0) Stage 2 of 5 (Device Configure) complete.
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0) Stage 1 of 5 (Device Prepare) scheduled...
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0) Stage 1 of 5 (Device Prepare) started...
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> (wlan0): device state change: need-auth -> prepare (reason 'none') [60 40 0]
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0) Stage 2 of 5 (Device Configure) scheduled...
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0) Stage 1 of 5 (Device Prepare) complete.
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0) Stage 2 of 5 (Device Configure) starting...
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> (wlan0): device state change: prepare -> config (reason 'none') [40 50 0]
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0/wireless): connection 'Hotspot' has security, and secrets exist. No new secrets needed.
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Config: added 'ssid' value 'autra-dev-laptop'
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Config: added 'mode' value '1'
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Config: added 'frequency' value '2412'
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Config: added 'key_mgmt' value 'NONE'
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Config: added 'wep_key0' value '<omitted>'
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Config: added 'wep_tx_keyidx' value '0'
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0) Stage 2 of 5 (Device Configure) complete.
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> (wlan0): supplicant interface state: scanning -> disconnected
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <warn> Couldn't disconnect supplicant interface: This interface is not connected.
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> (wlan0): disconnecting for new activation request.
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> (wlan0): device state change: config -> disconnected (reason 'none') [50 30 0]
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> (wlan0): deactivating device (reason 'none') [0]
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0) starting connection 'Hotspot'
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> (wlan0): device state change: disconnected -> prepare (reason 'none') [30 40 0]
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0) Stage 1 of 5 (Device Prepare) scheduled...
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <warn> Couldn't disconnect supplicant interface: This interface is not connected.
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Config: set interface ap_scan to 2
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> (wlan0): supplicant interface state: disconnected -> scanning
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0) Stage 1 of 5 (Device Prepare) started...
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0) Stage 2 of 5 (Device Configure) scheduled...
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0) Stage 1 of 5 (Device Prepare) complete.
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0) Stage 2 of 5 (Device Configure) starting...
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> (wlan0): device state change: prepare -> config (reason 'none') [40 50 0]
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0/wireless): connection 'Hotspot' has security, and secrets exist. No new secrets needed.
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Config: added 'ssid' value 'autra-dev-laptop'
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Config: added 'mode' value '1'
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Config: added 'frequency' value '2412'
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Config: added 'key_mgmt' value 'NONE'
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Config: added 'wep_key0' value '<omitted>'
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Config: added 'wep_tx_keyidx' value '0'
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Activation (wlan0) Stage 2 of 5 (Device Configure) complete.
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> (wlan0): supplicant interface state: scanning -> disconnected
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> Config: set interface ap_scan to 2
Nov 25 13:36:51 autra-dev-laptop NetworkManager[914]: <info> (wlan0): supplicant interface state: disconnected -> scanning
Nov 25 13:36:50 autra-dev-laptop avahi-daemon[586]: Received response from host 192.168.4.20 with invalid source port 56054 on interface 'eth1.0'
Nov 25 13:36:52 autra-dev-laptop avahi-daemon[586]: Invalid response packet from host fe80::8a51:fbff:feec:6cb9.
Nov 25 13:36:52 autra-dev-laptop avahi-daemon[586]: Invalid response packet from host 192.168.3.234.
Nov 25 13:36:52 autra-dev-laptop avahi-daemon[586]: Invalid response packet from host fe80::8a51:fbff:feec:6c68.
Nov 25 13:36:52 autra-dev-laptop avahi-daemon[586]: Invalid response packet from host 192.168.3.227.
Nov 25 13:37:17 autra-dev-laptop NetworkManager[914]: <warn> Activation (wlan0/wireless): Ad-Hoc network creation took too long, failing activation.
Nov 25 13:37:17 autra-dev-laptop NetworkManager[914]: <info> (wlan0): device state change: config -> failed (reason 'supplicant-timeout') [50 120 11]
Nov 25 13:37:17 autra-dev-laptop NetworkManager[914]: <warn> Activation (wlan0) failed for connection 'Hotspot'
Nov 25 13:37:17 autra-dev-laptop NetworkManager[914]: <info> (wlan0): device state change: failed -> disconnected (reason 'none') [120 30 0]
Nov 25 13:37:17 autra-dev-laptop NetworkManager[914]: <info> (wlan0): deactivating device (reason 'none') [0]
Nov 25 13:37:17 autra-dev-laptop NetworkManager[914]: <info> (wlan0): supplicant interface state: scanning -> disconnected
Nov 25 13:37:17 autra-dev-laptop NetworkManager[914]: <warn> Couldn't disconnect supplicant interface: This interface is not connected.

Note that ap mode seems to be supported by my wifi card :
10059 ◯ iw list
Wiphy phy0
 max # scan SSIDs: 20
 max scan IEs length: 195 bytes
 Coverage class: 0 (up to 0m)
 Device supports RSN-IBSS.
 Supported Ciphers:
  * WEP40 (00-0f-ac:1)
  * WEP104 (00-0f-ac:5)
  * TKIP (00-0f-ac:2)
  * CCMP (00-0f-ac:4)
 Available Antennas: TX 0 RX 0
 Supported interface modes:
   * IBSS
   * managed
   * AP
   * AP/VLAN
   * monitor

ProblemType: Bug
DistroRelease: Ubuntu 14.10
Package: network-manager 0.9.8.8-0ubuntu28
ProcVersionSignature: Ubuntu 3.16.0-24.32-generic 3.16.4
Uname: Linux 3.16.0-24-generic x86_64
ApportVersion: 2.14.7-0ubuntu8
Architecture: amd64
CurrentDesktop: Unity
Date: Tue Nov 25 13:54:16 2014
DistributionChannelDescriptor:
 # This is a distribution channel descriptor
 # For more information see http://wiki.ubuntu.com/DistributionChannelDescriptor
 canonical-oem-somerville-precise-amd64-20120703-2
InstallationDate: Installed on 2013-04-11 (593 days ago)
InstallationMedia: Ubuntu 12.04 "Precise" - Build amd64 LIVE Binary 20120703-15:08
IpRoute:
 default via 192.168.0.1 dev eth1 proto static
 192.168.0.0/21 dev eth1 proto kernel scope link src 192.168.4.25 metric 1
SourcePackage: network-manager
UpgradeStatus: Upgraded to utopic on 2014-11-14 (10 days ago)
mtime.conffile..etc.NetworkManager.NetworkManager.conf: 2014-11-25T13:50:26.688951
nmcli-dev:
 DEVICE TYPE STATE DBUS-PATH
 E8:E5:D6:97:28:E1 bluetooth disconnected /org/freedesktop/NetworkManager/Devices/8
 eth1 802-3-ethernet connected /org/freedesktop/NetworkManager/Devices/7
 wlan0 802-11-wireless connecting (configuring) /org/freedesktop/NetworkManager/Devices/0
nmcli-nm:
 RUNNING VERSION STATE NET-ENABLED WIFI-HARDWARE WIFI WWAN-HARDWARE WWAN
 running 0.9.8.8 connected enabled enabled enabled enabled enabled