Hello,
This is part of a known issue discussed here:
https://supportforums.cisco.com/discussion/11971001/java-strikes-again-login-error-javaioioexception-invalid-http-response
If you go check the bug info directly, you can see the versions that fix this:
https://tools.cisco.com/bugsearch/bug/CSCuj84421
Known Fixed Releases:
2.0(5f)
2.2(1b)
2.1(3b)
2.2(2c)
-Kenny