Not with soundfonts, though the SFZ-format does offer that possibility if I am correct. You can find out more about it at
sfzformat.com
With Polyphone you can export soundfonts as SFZ-files (plain text files and the samples are separate). From there you can open the SFZ-file with any text editor and then you can manually enter the so-called opcodes to give instructions other samples should be played when the pedal is used.
If you don't manage to find out how to do it, don't hesitate to ask here again. Maybe I can help you further when you've included the SFZ-file in the next post.
By the way, SFZ-files can be played with
SForZando.
