I tried wxCas on different machines and it keeps crashing due to wrong libiconv version:
Process:         wxcas [46068]
Path:            /Volumes/aMule-r10400-i386/Apps/wxCas.app/Contents/MacOS/wxcas
Identifier:      org.amule.wxCas
Version:         ??? (???)
Code Type:       X86 (Native)
Parent Process:  launchd [114]
Date/Time:       2010-12-17 13:44:53.298 +0100
OS Version:      Mac OS X 10.6.5 (10H574)
Report Version:  6
Interval Since Last Report:          729863 sec
Crashes Since Last Report:           2
Per-App Crashes Since Last Report:   1
Anonymous UUID:                      9B887C28-275D-413C-8663-02A0DB382BF2
Exception Type:  EXC_BREAKPOINT (SIGTRAP)
Exception Codes: 0x0000000000000002, 0x0000000000000000
Crashed Thread:  0
Dyld Error Message:
  Library not loaded: /opt/local/lib/libiconv.2.dylib
  Referenced from: /Volumes/aMule-r10400-i386/Apps/wxCas.app/Contents/MacOS/wxcas
  Reason: Incompatible library version: wxcas requires version 8.0.0 or later, but libiconv.2.dylib provides version 7.0.0
Binary Images:
0x8fe00000 - 0x8fe4162b  dyld 132.1 (???) <39AC3185-E633-68AA-7CD6-1230E7F1CEF4> /usr/lib/dyld
But:
$ otool -L /opt/local/lib/libiconv.2.dylib 
/opt/local/lib/libiconv.2.dylib:
	/opt/local/lib/libiconv.2.dylib (compatibility version 8.0.0, current version 8.0.0)
EDIT: here it is...
$ otool -L /usr/lib/libiconv.2.dylib 
/usr/lib/libiconv.2.dylib:
	/usr/lib/libiconv.2.dylib (compatibility version 7.0.0, current version 7.0.0)
So, what is looking for? For local installation of libiconv? Apple won't never update it...