Bug#584572: symbol lookup error: undefined symbol

[Edward Allcutt <emallcut@gleim.com>]

Package: libstdc++6
Version: 4.5.0-5
Severity: critical
Tags: experimental

After upgrading libstdc++6 this morning, various C++ software began
failing. The original version upgraded from was 4.5.0-4 so the problem
appears to be introduced in this specific version.

Following is a transcript of reproducing the problem.
=====================================================
# apt-cache policy libstdc++6
libstdc++6:
  Installed: 4.4.4-1
  Candidate: 4.4.4-1
  Version table:
     4.5.0-5 0
        700 http://dpkg.teamgleim.com rc-buggy/main Packages
     4.4.4-4 0
        800 http://dpkg.teamgleim.com sid/main Packages
 *** 4.4.4-1 0
        900 http://dpkg.teamgleim.com squeeze/main Packages
        100 /var/lib/dpkg/status
# aptitude install libstdc++6/experimental
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Reading extended state information... Done
Initializing package states... Done       
The following packages will be upgraded:
  libstdc++6 
1 packages upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Need to get 345kB of archives. After unpacking 16.4kB will be freed.
Do you want to continue? [Y/n/?] 
Writing extended state information... Done
Get:1 http://dpkg.teamgleim.com rc-buggy/main libstdc++6 4.5.0-5 [345kB]
Fetched 345kB in 0s (8,694kB/s)
Reading changelogs... Done
(Reading database ... 137430 files and directories currently installed.)
Preparing to replace libstdc++6 4.4.4-1 (using .../libstdc++6_4.5.0-5_i386.deb) ...
Unpacking replacement libstdc++6 ...
Setting up libstdc++6 (4.5.0-5) ...
Reading package lists... Done             
Building dependency tree       
Reading state information... Done
Reading extended state information... Done
Initializing package states... Done       
Writing extended state information... Done

Current status: 0 updates [-1].
# apt-cache policy libstdc++6
apt-cache: symbol lookup error: /usr/lib/libstdc++.so.6: undefined symbol: _ZNSt7num_getIcSt19istreambuf_iteratorIcSt11char_traitsIcEEE2idE, version GLIBCXX_3.4
# 
=====================================================

I'm going to downgrade to the version in squeeze now, but I can
reupgrade any time if more details are needed.

-- System Information:
Debian Release: squeeze/sid
Architecture: i386 (i686)

Kernel: Linux 2.6.32-5-686 (SMP w/2 CPU cores)
Locale: LANG=en_US.utf8, LC_CTYPE=en_US.utf8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages libstdc++6 depends on:
ii  gcc-4.5-base                  4.5.0-5    The GNU Compiler Collection (base 
ii  libc6                         2.10.2-9   Embedded GNU C Library: Shared lib
ii  libgcc1                       1:4.5.0-5  GCC support library

libstdc++6 recommends no packages.

libstdc++6 suggests no packages.

-- no debconf information