Check if variable is numeric (Net.Data)

I do have the manuals for V5R2 and I know I can use this function DTW_ISNUMERIC;
however, we will not be in V5R2 until next week and I need to work this out
today.  To add more complexity, the manuals I can find are telling me that I can
use the referred function but is giving me an error:

NET.DATA Error: FUNCTION block DTW_ISNUMERIC not found.

I guess is because we are on V4R5... if not, how can I do this check?

Thanks,
Peter Vidal
Pall Aeropower Corp.
SR Programmer Analyst
WWW.Pall.com / 727-539-8448, x2414

"A good player makes himself look good;
a great player makes the team look good."
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