Interface programming

[mantri@ponder.csci.unt.edu (Ramesh S. Mantri)]

Hi,
	Need help with interface programming. I need to invoke a 
Square Root function in a program. So I tried interfacing to Fortran
as follows :
	procedure SOMEPROC is
	  package FORT_LIB is
	    function SQRT(X:FLOAT) return FLOAT;
	  private
	    pragma INTERFACE(FORTRAN, SQRT);
	  end FORT_LIB;
	  NUM : INTEGER;
	  NUMROOT : FLOAT;
	begin
	  GET(NUM); 
	  NUMROOT := SQRT(FLOAT(NUM));
	end SOMEPROC;
It is displaying a warning at the "pragma" line, and declaring "SQRT"
as and undefined identifier, in the line "NUMROOT := SQRT(FLOAT(NUM));".
If you have time, please take the trouble of informing me as to how to
rectify this. Also, the warning dispayed at the "pragma" line reads
approximately as : "... parameter types. SYSTEM.ADDRESS expected..."
Thanks for your patience.
--- Ramesh Mantri