>In order to be truly useful, I need something that I can use in VFP that will IDEALLY let me specify mode and algorithm AND also let me specify an Input Vector (sometimes referred to as crypt.IV or crypt-4). At a minimum, I must know what mode/algo/IV the control or class uses - something I can't seem to figure out for CryptPak.
>
>So, after all that... anyone have any suggestions?

I have no experience with PHP/Perl and other OS outrside of Windows. If it is not Windows on one end, the Win Crypto API will not do for you. Maybe PGP will help as they have implementations for different OS and very strong cryptography.

http://www.pgp.com/

See also other possible options:
http://www.f-secure.com/
http://www.entrust.com/
http://www.schneier.com/blowfish.html