Variable in fix deform

Hello
   I am trying to use a variable to define strain rate instead of giving hard code value in fix_deform command, but result is coming totally different, any one has tried this before, is there any way around for it or those parameter values should be hard coded only.
fix 2 all deform 1 xy erate 0.01 remap v (erate is hard codes as 0.01)
fix 2 all deform 1 xy erate v_erat remap v (value of erate is defined as a variable 'v_erat')

Regards
Abhishek

Hello
I am trying to use a variable to define strain rate instead of giving
hard code value in fix_deform command, but result is coming totally
different, any one has tried this before, is there any way around for it
or those parameter values should be hard coded only.
fix 2 all deform 1 xy erate 0.01 remap v (erate is hard codes as
0.01)
fix 2 all deform 1 xy erate v_erat remap v (value of erate is
defined as a variable 'v_erat')

does it say anywhere in the fix deform documentation that such
a construct is supported?

axel.