linux branch build broken - need assistance please

The linux build is broken now .. any help greatly appreciated. Snippet 
from the log file...
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c++ -o mozilla-bin -I/usr/X11R6/include -fno-rtti -fno-exceptions -Wall 
-Wconver
sion -Wpointer-arith -Wbad-function-cast -Wcast-align 
-Woverloaded-virtual -Wsyn
th -Wno-ctor-dtor-privacy -pedantic -Wno-long-long -pthread -pipe  
-DNDEBUG -DTR
IMMED -O -DWIDGET_DLL=\"libwidget_gtk.so\" 
-DGFXWIN_DLL=\"libgfx_gtk.so\" -I/usr
/lib/glib/include -I/usr/X11R6/include  nsAppRunner.o nsWindowCreator.o 
showOSAl
ert.o nsSigHandlers.o nsNativeAppSupportGtk.o 
nsNativeAppSupportBase.o    -L../.
./dist/bin -L../../dist/lib  -lgkgfx -lmpfilelocprovider_s -ljsj  
-L../../dist/b
in -lmozjs  -L../../dist/bin -lxpcom 
-L/builds/client/linux22/seamonkey/mozilla/
dist/lib -lplds4 -lplc4 -lnspr4 -lpthread -ldl -lc   -L/usr/lib 
-L/usr/X11R6/lib
 -lgtk -lgdk -rdynamic -lgmodule -lglib -ldl -lXi -lXext -lX11 -lm -ldl 
-lm  -lc
    
../../dist/bin/libgkgfx.so: undefined reference to 
`nsRenderingContextImpl::UseB
ackbuffer(int *)'
collect2: ld returned 1 exit status
gmake[3]: *** [mozilla-bin] Error 1
gm
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