arbitrary length arithmetic on servers

carrying on from my last post, i managed to get some free server space and
ran a few test scripts, all seemed fine. but i cannot seem to get the
'arbitrary length' arithmetic feature to be recognised by the server - the
bcmul, bcsub, bcadd commands etc.

i seem to remember having to enable this feature in the config file when i
installed php on my machine, but have no clue how to do this on a server.
would the server company enable this or is there some way i can do it
myself?

thanks


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