Having such method sequence in class as showed below, SendMessage() always calls the method with no parameter, no matter what parameter it sends:

//No parameter
public void Method(){}

// String paprameter.
public void Method(string str){}

If we switch method's places in script, SendMessage() works as expected, regarding parameter's variable.

Reproducible on 4.6 - 5.4 versions.

Repro steps:
1. open "SendMessageTest.zip".
2. open "Test1" scene and press play. Press keyboard buttons according to instructions. Observe that sending different parameters, always getting "No parameters" function message.
3. open "Test2" scene and press play. Press the same buttons and observe, that different parameters are recognized as expected.

The only difference is the methods sequence in scripts.

Expected result: should work despite the methods sequence.

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Won't fix:
This issue will not be fixed, because SendMessage() does not try to handle method overloads, for performance reasons. We have updated documentation to reflect this.