objc runtime: cannot find class NSDPSContext

[Pascal Bourguignon]

I just compiled and installed:
ffcall-1.8d/
gnustep-make-1.6.0/
gnustep-base-1.6.0/
gnustep-gui-0.8.5/
gnustep-back-0.8.5/

and after having configured, compiled and installed gnustep-back with:
b=xlib ; ./configure --prefix=/local/GNUstep/ --enable-graphics=$b 
--with-name=$b && make && make install ; defaults write NSGlobalDomain 
GSBackend libgnustep-xlib 

Launching GWorkspaces gives this error:

[pascal@thalassa gnustep-back-0.8.5]$  
/local/GNUstep/System/Applications/GWorkspace.app/GWorkspace 
objc runtime: cannot find class NSDPSContext
Aborted

Could it be because the library has no .a or .so extension?
What's happening?

[pascal@thalassa gnustep-back-0.8.5]$ file 
/local/GNUstep/System/Library/Bundles/libgnustep-xlib.bundle/ix86/linux-gnu/gnu-gnu-gnu/libgnustep-xlib
/local/GNUstep/System/Library/Bundles/libgnustep-xlib.bundle/ix86/linux-gnu/gnu-gnu-gnu/libgnustep-xlib:
 ELF 32-bit LSB shared object, Intel 80386, version 1, not stripped

[pascal@thalassa gnustep-back-0.8.5]$  defaults read NSGlobalDomain GSBackend
NSGlobalDomain GSBackend 'libgnustep-xlib'

-- 
__Pascal_Bourguignon__                   http://www.informatimago.com/
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