when I use pack's 'f' option the value changes when read in by the SAS program on the other end

I'm thinking that either:

a) pack's 'f' option is behaving incorrectly
or
b) the "SAS program" is misreading its input.

Is there a third possibility ?
If not, an example showing us what pack's 'f' option produces for a specific value, and the changed value that the SAS program reads would help us to determine where the problem lies.

The ouput of perl -V might also be helpful.

Cheers,
Rob