after getting the appended install errors, launching various windowed apps fails, e.g.:
leafpad: symbol lookup error: /usr/lib/libgdk-x11-2.0.so.0: undefined symbol: g_malloc_n

same for epdfview

previously, I got the same error from firefox (both shiretoko and unrebranded mozilla firefox 3.6.3); after posting this I'll restart firefox to see if it's affected in this direct test of the issue. If it works I'll post that info shortly, but otherwise assume that it's affected.

Also, previously I tried to ldconfig, but that didn't remedy.

gtk+-2.20.1.tazpkg 100% |*******************************| 1597k 00:00:00 ETA

Installation of : gtk+-2.20.1
================================================================================
Copying gtk+-2.20.1... [ OK ]
Extracting gtk+-2.20.1... 3195 blocks
Extracting the pseudo fs... (lzma) 10444 blocks
Saving configuration files for gtk+... [ OK ]
Installing gtk+... [ OK ]
Removing old gtk+... [ OK ]
Removing all tmp files... [ OK ]
Processing post-install commands...
/usr/bin/gtk-query-immodules-2.0: symbol lookup error: /usr/lib/libgtk-x11-2.0.so.0: undefined symbol: g_malloc_n
g_module_open() failed for /usr/lib/gtk-2.0/2.10.0/loaders/libpixbufloader-ani.so: /usr/lib/gtk-2.0/2.10.0/loaders/libpixbufloader-ani.so: undefined symbol: g_try_malloc_n
g_module_open() failed for /usr/lib/gtk-2.0/2.10.0/loaders/libpixbufloader-png.so: /usr/lib/gtk-2.0/2.10.0/loaders/libpixbufloader-png.so: undefined symbol: g_malloc0_n
================================================================================
gtk+ (2.20.1) is installed.