Could not load dynamic library Plugin_TheoraVideoSystem

I compiled Ogre from source on Linux, then libtheoraplayer and ogre video plugin.
then I put plugin name in plugins.cfg. There shouldn't be anything wrong with the paths.
but when I ran the executable after I built it, I got this runtime error:

Loading library /usr/local/lib/Plugin_TheoraVideoSystem
An exception has occured : OGRE EXCEPTION(7:InternalErrorException): Could not load dynamic library /usr/local/lib/Plugin_TheoraVideoSystem. System Error: /usr/local/lib/Plugin_TheoraVideoSystem.so: undefined symbol: _ZTI16TheoraDataSource in DynLib::load at /home/mohammad/workspace/ogre/ogre_src_v1-7-2/OgreMain/src/OgreDynLib.cpp (line 91)

The Ogre.log has nothing more helpful.

Any idea why I'm getting this? Thanks in advance!

any Idea?

1) I haven't tested the plugin on ogre 1.7
2) I haven't tested it under linux much

so I can't be of much use in this problem.

however what I can see here is probably a linking error. maybe you forgot to link libtheoraplayer?

Kreso

however what I can see here is probably a linking error. maybe you forgot to link libtheoraplayer?
yes, you right, I forgot to link libtheoraplayer

what an amateurish mistake (actually, i'm an amateur )

thank you