LinuxQuestions.org - [SOLVED] Browsing for local file segfaults Firefox

On Firefox 11.0, selecting the file browser button (in order to select a local file to upload) segfaults Firefox. The problem appears limited to Firefox; Opera 11.62 works fine.

Opening Firefox in a terminal I see upon launch "Gtk-WARNING **: Locale not supported by C library. Using the fallback 'C' locale", and a segfault message when it crashes. I'm not convinced that the locale issue is is related to the problem, but it's the only clue I have, so here's the output of locale:

$ locale
locale: Cannot set LC_ALL to default locale: No such file or directory
LANG=en_US.UTF-8
LC_CTYPE=en_US.UTF-8
LC_NUMERIC=es_HN.UTF-8
LC_TIME=en_US.UTF-8
LC_COLLATE=en_US.UTF-8
LC_MONETARY=es_HN.UTF-8
LC_MESSAGES=en_US.UTF-8
LC_PAPER=es_HN.UTF-8
LC_NAME=es_HN.UTF-8
LC_ADDRESS=es_HN.UTF-8
LC_TELEPHONE=es_HN.UTF-8
LC_MEASUREMENT=es_HN.UTF-8
LC_IDENTIFICATION=es_HN.UTF-8
LC_ALL=

This isn't my box, and the user can't give my any idea on when the problem started or what update or other change might be associated with it. For what it's worth, the most recent updates are:

# rpm -qa --last
flash-plugin-11.2.202.228-release Mon Apr 9 19:10:24 2012
libwxgtku2.8-2.8.12-69mib2009.1 Mon Apr 9 08:51:06 2012
qca2-plugin-openssl-2.0.2-6.1111917.69.1mib2009.1 Mon Apr 9 08:50:10 2012
rootcerts-java-20120218.00-69.1mib2009.1 Mon Apr 9 08:50:09 2012
libpostproc51-0.7.11-69.1mib2009.1 Mon Apr 9 08:50:09 2012
wxgtk2.8-2.8.12-69mib2009.1 Mon Apr 9 08:50:07 2012
libqca2-2.0.2-6.1111917.69.1mib2009.1 Mon Apr 9 08:50:06 2012
firefox-en_GB-11.0-69.1mib2009.1 Mon Apr 9 08:49:06 2012
firefox-11.0-69.1mib2009.1 Mon Apr 9 08:48:54 2012
libnss3-3.13.3-69.2mib2009.1 Mon Apr 9 08:48:44 2012
nss-3.13.3-69.2mib2009.1 Mon Apr 9 08:48:40 2012
rootcerts-20120218.00-69.1mib2009.1 Mon Apr 9 08:48:32 2012
sqlite3-tools-3.7.11-69.1mib2009.1 Mon Apr 9 08:48:27 2012
libsqlite3-devel-3.7.11-69.1mib2009.1 Mon Apr 9 08:48:26 2012
libswscaler0-0.7.11-69.1mib2009.1 Mon Apr 9 08:48:25 2012
libavutil50-0.7.11-69.1mib2009.1 Mon Apr 9 08:48:23 2012
libnspr4-4.9.0-69.1mib2009.1 Mon Apr 9 08:48:22 2012
libsqlite3_0-3.7.11-69.1mib2009.1 Mon Apr 9 08:48:20 2012
bleachbit-0.8.7-69.1mib2009.1 Fri Apr 6 18:08:35 2012
bind-9.6.2-0.1mdv2009.1 Thu Jan 19 14:49:52 2012
(snip)

Distro is Mandriva 2009.1 -- old, but the box owner likes it.

Searching the web and this forum for "firefox crash file browse" didn't turn up any useful hits.

Any thoughts on what I should be looking at next to fix this annoyance?