FB 1.5
XP Pro SP 2

I'm getting this error and cannot understand why:

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Seed packet
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ISC ERROR CODE:335544663



ISC ERROR MESSAGE:

Too many concurrent executions of the same request


---------------------------
OK
---------------------------

This happens on a line of code in Delphi 7 that creates a TIB_Cursor
that calls a procedure that converts various units - say from metric
to English. The SQL is: "Select OUTNUM from P_CONVERTNUM
(:INNUM, :INUNIT, :OUTUNIT)"

I have read about this error in relation to triggers that call an SP
recursively, however in my case this SP is just called one time and
the SP itself is just a series of "IF... ELSE..." statements to
cover each of the possible conversions, i.e. it doesn't recursively
call itself.

Is there something else that can cause this error?

Thanks,

Rick