synaptic crashed with SIGSEGV in debListParser::LoadReleaseInfo()

Crashed while trying to update. I've also been getting apt-xapian-index crashes since running sudo update-apt-xapian-index trying to fix the problem of Synaptic's quick search box not working. (packages are filtered out even when typing their exact name into the quick search box, even though they can be found by scrolling through the list alphabetically).

Description: Ubuntu oneiric (development branch)
Release: 11.10

synaptic:
  Installed: 0.75.2ubuntu6
  Candidate: 0.75.2ubuntu6
  Version table:
 *** 0.75.2ubuntu6 0
        500 http://archive.ubuntu.com/ubuntu/ oneiric/universe amd64 Packages
        100 /var/lib/dpkg/status

ProblemType: Crash
DistroRelease: Ubuntu 11.10
Package: synaptic 0.75.2ubuntu6
ProcVersionSignature: Ubuntu 3.0.0-11.18-generic 3.0.4
Uname: Linux 3.0.0-11-generic x86_64
NonfreeKernelModules: fglrx
ApportVersion: 1.23-0ubuntu1
Architecture: amd64
Date: Tue Sep 27 01:25:00 2011
ExecutablePath: /usr/sbin/synaptic
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Release amd64 (20110427.1)
ProcCmdline: /usr/sbin/synaptic
SegvAnalysis:
 Segfault happened at: 0x7fd1cef18699 <_ZN13debListParser15LoadReleaseInfoERN8pkgCache15PkgFileIteratorER6FileFdSs+649>: mov %eax,0x4(%rbp)
 PC (0x7fd1cef18699) ok
 source "%eax" ok
 destination "0x4(%rbp)" (0x7fd1bbd70004) not located in a known VMA region (needed writable region)!
SegvReason: writing unknown VMA
Signal: 11
SourcePackage: synaptic
StacktraceTop:
 debListParser::LoadReleaseInfo(pkgCache::PkgFileIterator&, FileFd&, std::string) () from /usr/lib/libapt-pkg.so.4.11
 debPackagesIndex::Merge(pkgCacheGenerator&, OpProgress*) const () from /usr/lib/libapt-pkg.so.4.11
 ?? () from /usr/lib/libapt-pkg.so.4.11
 pkgCacheGenerator::MakeStatusCache(pkgSourceList&, OpProgress*, MMap**, bool) () from /usr/lib/libapt-pkg.so.4.11
 ?? ()
Title: synaptic crashed with SIGSEGV in debListParser::LoadReleaseInfo()
UpgradeStatus: Upgraded to oneiric on 2011-09-20 (6 days ago)
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