Mocked generic method returns incorrect mocked type

[ogray58]

Version
JMockit: 1.33
JUnit: 4.11
Java: 1.8.0_66

Description
A mocked generic method will return an instance of the mocked class, instead of a mock matching the type of the parameter. This can be demonstrated with the code below, which produces the following error when run:
java.lang.ClassCastException: package.Class$TestClass cannot be cast to java.lang.String

Code to Reproduce

@Mocked private TestClass mockedTestClass = null;

@Test
public void test()
{
	System.out.println(new TestClass().testMethod("test"));
}

private static class TestClass
{
	public <R> R testMethod(R value)
	{
		return value;
	}
}

[ogray58]

I also have this case (ATest.failingTest() in the zip below) which fails under the same versions and I can't seem to condense any further. It does involve a generic method so I'm wondering if it has the same cause as this bug, but in this case the generic method does seem to return the correct type, but the test fails later due to an NPE which happens immediately after a null check on the returned object.

EDIT: Condensed the example case somewhat. Does seem related to this generics issue as removing a generic parameter from a method does make it pass. The issue does seem to manifest itself slightly differently than the case described above though.

Zipped code to reproduce