[Valgrind-users] "the `impossible' happened" - error

[Geert F. <gee...@es...>]

hello, valgrind died with the following message:

-----------------------------------------
disInstr: unhandled opcode 0xE0 then 0x19

valgrind: the `impossible' happened:
    unhandled x86 opcode
Basic block ctr is approximately 50850000

sched status:

Thread 1: status = Runnable, associated_mx = 0x0, associated_cv = 0x0
==11282==    at 0x406F1B48: ???
==11282==    by 0x80F3690: GRV::bDraw(bool) (GRV.cpp:97)
==11282==    by 0x80F6E98: GRVCNeuron::bDraw(bool) (GRVCNeuron.cpp:90)
==11282==    by 0x807E69C: GBrain::bRun() (GBrain.cpp:129)

Please report this bug to: js...@ac...
------------------------------------------

any idea what is going wrong? is this an error in valgrind (i doubt it 
as my program crashes without valgrind as well), or an error in GCC (i'm 
using 3.2.2), or (most likely) my mistake? the code where he crashes on 
makes some heavy use of virtual functions and overloaded function. what 
should i put i my bugreport?

greets,
geert.