Since I havn't really started a readme of any sort for KoalaMud, I'll put this information here for now.
Currently KoalaMud depends on the following:
Qt v3.0.0 or above
ZThread 2.2.10
MySQL 3.23 or above

KoalaMud is tested against:
Qt v3.0.5
ZThread 2.2.10
MySQL 3.23.51
gcc version 2.95.3 20010315 (release)

Where to get them:
Qt:  www.trolltech.com
ZThread: http://www.cs.buffalo.edu/~crahen/projects/zthread/
MySQL: www.mysql.com

Before reporting a bug, please make sure that you are using sufficiently recent versions of the dependant libraries.  Eventually there will be more variety to the officially supported platforms, but currently the development rate is very high and more official platforms would only slow things down.