The comparison operator bug

Here's another example of Excel's worksheet functions not operating in the same way as their VBA equivalents.

In cell A1 I put "ABCdef" and gave the cell a range name "AAAA".
In cell B1 I put "ABCDEF" and gave the cell a range name "BBBB"
In cell C1 I put the formula "=AAAA=BBBB", which gave a result of "TRUE".

Below is an extract from a workbook which uses the above formula to prove that the result is zero, and then the same figures in the MOD function generating an error.

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In VBA I created the following sub routine:
  Sub a()
MsgBox Range("AAAA") = Range("BBBB")
End Sub
It gave the answer "FALSE".
Conclusion: The comparison operator "=" does not work in the same way on a spreadsheet and in VBA.