Issue1456

While testing Jython 2.5.1rc1 with PyAMF 0.5 trunk (r2754) I'm getting unexpected 
errors that don't show up in CPython:

$ jython
Jython 2.5.1rc1 (Release_2_5_1rc1:6736:6741, Sep 1 2009, 10:37:37) 
[Java HotSpot(TM) 64-Bit Server VM (Apple Inc.)] on java1.6.0_13
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> import pyamf
>>> pyamf.register_package(sys, 'com.example.test')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "pyamf/__init__.py", line 1680, in register_package
    classes = filter(check_attr, [get(x) for x in keys])
  File "pyamf/__init__.py", line 1647, in <lambda>
    get = lambda x: getattr(module, x)
AttributeError: write-only attr: trace

$ python
Python 2.5.1 (r251:54863, Feb  6 2009, 19:02:12) 
[GCC 4.0.1 (Apple Inc. build 5465)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> import pyamf
>>> pyamf.register_package(sys, 'com.example.test')
{}

Note that the same thing happens with Jython 2.5 final:

$ ../jython2.5.0/bin/jython 
Jython 2.5.0 (Release_2_5_0:6476, Jun 16 2009, 13:33:26) 
[Java HotSpot(TM) 64-Bit Server VM (Apple Inc.)] on java1.6.0_13
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> import pyamf
>>> pyamf.register_package(sys, 'com.example.test')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "pyamf/__init__.py", line 1680, in register_package
    classes = filter(check_attr, [get(x) for x in keys])
  File "pyamf/__init__.py", line 1647, in <lambda>
    get = lambda x: getattr(module, x)
AttributeError: write-only attr: trace

This was due to our sys module being a weird Java integration object and the Java integration layer making set-only shorthand bean properties for the sys.settrace/profile functions. I disabled the props in r7020 with a hack

Hopefully one day we can redo sys to be a simpler real Python module