For what i can see the amule you use was compiled with wx that supports unicode, thats why when you did ldd amule you got:
libwx_gtk2u_adv-2.6.so.0 => /usr/lib/libwx_gtk2u_adv-2.6.so.0 (0x00002aaaab4eb000)
libwx_gtk2u_core-2.6.so.0 => /usr/lib/libwx_gtk2u_core-2.6.so.0 (0x00002aaaab6a5000)
and you said that you have it installed so what wardevil said isnt apliable.
Now what appears to me is that the amule you installed was compiled at least with a diferent qt3 version from the one you use, or if that isnt the case there is a library that amule needs that you have but a different release.
This is the type of problem i see with the type of errors like yours, yet im a Mandriva contrib developer so i cant give much more help regarding debian based filesystems.