This works for me.

 Code:
Break on

$uid = "12345"

If IsNumeric($uid) = 1
	? "UID is numeric."
Else
	? "UID is NOT numeric."
EndIf

;Function       IsNumeric()
;
;Author:	apronk
;
;Action:
;		Determines whether an expression is a valid numeric type.
;
;Syntax:
;		IsNumeric($strInput)
;
;Version:
;		1.0 December 11th 2009.
;		Initial post.
;
;Parameters:
;		$strInput - Required.
;			The input string to evaluate.
;
;Returns:
;		1 if the input is Numeric
;		0 if the input is NOT Numeric.
;
;Dependencies
;		No known dependencies
;
;KiXtart:
;		Developed and tested KiXtart 4.61 and Windows 7 Ultimate.
;
;Example(s):
;		Break on
;		$rc = IsNumeric("2000")
;		? $rc
;
;Code:
Function IsNumeric($strInput)
	Dim $sc, $rc
	$sc = CreateObject("ScriptControl")
	$sc.Language = "VBScript"
	$rc = $sc.Eval('IsNumeric("' + $strInput + '")')
	If $rc = -1
		$IsNumeric = 1
	Else
		$IsNumeric = 0
	EndIf
EndFunction
_________________________
Mart

- Chuck Norris once sold ebay to ebay on ebay.