In your module write

    use Set::Infinite 0.43;
[download]

instead of just

    use Set::Infinite;
[download]

That way the tester will get the error message:

    Set::Infinite version 0.43 required--this is only version 0.41 at 
+-e line 1.
[download]

That might give the tester enough hints to update the prerequisite before submitting the bug report. On the other hand, I think the tester must have already ignored the warning from MakeMaker, so it is questionable if this would help. But I think it is more likely that the actual test failure would be read than the MakeMaker output.