Nested Application.Evaluate not working

Hello,
I've encountered a quite specific problem with the Application.Evaluate method. Apparently nested calls to it do not work (code execution stops without any message). I've attached a simple file that pinpoints the problem. Execution of "Sub test" in the Sheet1 object should display a MsgBox showing "10". However, nothing happens. I'm using Excel 2010.
Any help would be appreciated.

Hi kaktus018,
try it

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Thanks for the quick replies. I know that Evaluate is not necessary for the posted sample code to work. It is just meant to show the problem I want to solve.
I've written a numeric modul in VBA and recently added an optimization algorithm. Now this algorithm needs to evaluate an objective function (let it be fun1) and find the minimum of it. For that purpose the method needs a function-String which is then evaluated using Application.Evaluate (it can also be something like "x^2+y^2", no need to be a UDF this way). This works fine as long as there are no further calls to Evaluate inside fun1.
Now I want to solve a differential equation inside fun1. My solver uses the same strategy here - it evaluates a function-String with Application.Evaluate. So fun1 is called by Evaluate and itself uses Evaluate again. This means a nested structure and is exactly my problem.
Is there no way to make it work that way?

I now came up with a workaround. Directly evaluating the string in a cell seems to work with Application.Evaluate. So i wrote a function that adds a temporary sheet to the workbook and uses cell "A1" to evaluate the string. It then returns the result of the evaluation. This way I can implement it the same way as Application.Evaluate.
Here is the function:

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The following sub deletes the temporary sheet after computation is completed:

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Well, lets say I've got the function "x^2" I want to integrate. So I pass the string "x^2" on to my solver and tell it that "x" is the variable. The solver than replaces "x" at every calculation point with a number and evaluates the function.
The function string can of course also contain a UDF. That way I don't need to explicitly implement "x^2" or any other function in a VBA function (and I don't know how Application.Run would handle nested calls).

This code as well uses Evaluate. I haven't tried it but I suppose when there is another call to Evaluate by myUDF, the code won't work.