Pity he doesn't give more detail: different machines are mentioned, but are we talking about different software platforms too? If not, for example they both use the Java MessageDigest implementation, then the problem might well be an encoding problem in the conversion from a
String to a byte[] (hint: enforce a standard encoding such as UTF-8 so you're independent of what the platform default encoding happens to be). The MD5 algorithm wouldn't help at all in that case. OTOH if they're different software platforms, perhaps with a broken MD5 implementation, then the algorithm might well help.
- Peter