ya u can, but only the problem will be if X94) is containing spaces and if u try to check some condition clause like the varibale of PIC 9(4) is compared with ZEROES, like
01 var1 pic X(4) value SPACES.
02 var2 redefines VAR1 pic 9(04).
and in code
if VAR2 is greater than ZEROES
...then i think in this case u will get run time erro like OC7.
correct me if i m wrong.