Its possible.
se38->create a program of type subroutine pool(say zsmm_create_fcurr_to_lcurr ) and create the form as I said. Remember to uncheck Fixed point arithmetic in this subroutine pool.
Then call the form.
PERFORM currency_to_local(zsmm_create_fcurr_to_lcurr)
USING fc_waers
lc_waers
netpr
kdatu
kkurs
kufix.
What is the type of re_outtab_purchdoc?