Define Sheet Level Name Range Code

In general defining Sheet Level Name Ranges works fine with me, most of the times I use something like shown in the code below.

However, I have discovered that apparently the successfull execution depends on the sheet-name format itself

The code below works perfectly fine with worksheet names like "234", "cas422", etc
but it fails to work with worksheet names like: "C12c", "eh34h4". It seems to me - but I am not sure of being able to generalize this - as if it works when the name contains [numbers][letters] or [letter][numbers], but it fails when it contains a mixture of both like [numbers][letters][numbers] or [letters][numbers][letters] .... in case of a failure of the code, I go into debug mode and simply rename the sheet, then everything's fine again.

Am I the only one to experience such difficulties? (I run Excel 2003 with SP3 on Windows XP) Or would a different code prevent this kind of trouble?

I think, I could write a workround, but before doing so I'd rather like to ask if I am doing something wrong here?


ActiveWorkbook.Names.Add name:=wks.name & "!myTime", RefersToR1C1:="=" & wks.name & "!R1C1:R5C8"