iSeries (AS/400) Database File: password encryption I am helping with a project in which an old software system on an iSeries is having a brand new .NET UI applied to it.  It's going well... except...

In order to allow users to login and maintain compatibility with the existing software installation, we need to figure out what encryption/hashing method the previous vendor was using without access to their source code.

I have a file with an ID and Password column.  The password column appears to contains only 16 characters per record, all binary.

Part of the previous vendor system was written in native green screen on the 400, and part of it was written in Microsoft ASP.Net.  

What type of encryption or hash would be:


Used by an AS/400 or iSeries Green Screen app, and
Used by a Microsoft .NET app, and
Output a consistent 16 binary bytes, regardless of input length


Pointers much appreciated.  Thanks!
Wikipedia has a list of cryptographic hash functions, together with their output size. 16 bytes are 128 bits. From the list, the following ones could be candidates:


MD2, MD4, MD5
RIPEMD / RIPEMD-128
HAVAL-128


The most probable one would be MD5, so start with this.