Description of problem:

ipa netgroup-add returns an internal error when both --desc and
--addattr=description are used.

# ipa netgroup-add testng-002 --desc=testng-002 --nisdomain=mynisdom
--addattr=description=DESCRIPTION
ipa: ERROR: an internal error has occurred

Version-Release number of selected component (if applicable):

389-ds-base-1.2.10.1-1.el6.x86_64
389-ds-base-libs-1.2.10.1-1.el6.x86_64
ipa-server-2.2.0-102.20120220T2339zgit7fe095c.el6.x86_64

How reproducible:
always

Steps to Reproduce:
1.  <setup ipa server>
2.  kinit admin
3.  ipa netgroup-add testnetgroup --desc=test --addattr=description=testdesc

Actual results:

# ipa netgroup-add testnetgroup --desc=test --addattr=description=testdesc
ipa: ERROR: an internal error has occurred

Expected results:

I would expect a message more like this to be returned:

# ipa netgroup-add testnetgroup --desc=test --desc=testdesc
ipa: ERROR: invalid 'description': Only one value is allowed

Additional info:

log entries from /var/log/httpd/error_log:

[Wed Feb 22 13:41:01 2012] [error] ipa: ERROR: non-public: AttributeError:
'unicode' object has no attribute 'extend'
[Wed Feb 22 13:41:01 2012] [error] Traceback (most recent call last):
[Wed Feb 22 13:41:01 2012] [error]   File
"/usr/lib/python2.6/site-packages/ipaserver/rpcserver.py", line 232, in
wsgi_execute
[Wed Feb 22 13:41:01 2012] [error]     result = self.Command[name](*args,
**options)
[Wed Feb 22 13:41:01 2012] [error]   File
"/usr/lib/python2.6/site-packages/ipalib/frontend.py", line 438, in __call__
[Wed Feb 22 13:41:01 2012] [error]     ret = self.run(*args, **options)
[Wed Feb 22 13:41:01 2012] [error]   File
"/usr/lib/python2.6/site-packages/ipalib/frontend.py", line 696, in run
[Wed Feb 22 13:41:01 2012] [error]     return self.execute(*args, **options)
[Wed Feb 22 13:41:01 2012] [error]   File
"/usr/lib/python2.6/site-packages/ipalib/plugins/baseldap.py", line 903, in
execute
[Wed Feb 22 13:41:01 2012] [error]     self.process_attr_options(entry_attrs,
None, keys, options)
[Wed Feb 22 13:41:01 2012] [error]   File
"/usr/lib/python2.6/site-packages/ipalib/plugins/baseldap.py", line 833, in
process_attr_options
[Wed Feb 22 13:41:01 2012] [error]     entry_attrs.setdefault(attr,
[]).extend(adddict[attr])
[Wed Feb 22 13:41:01 2012] [error] AttributeError: 'unicode' object has no
attribute 'extend'
[Wed Feb 22 13:41:01 2012] [error] ipa: INFO: admin@TESTRELM.COM:
netgroup_add(u'testnetgroup', description=u'test',
addattr=(u'description=testdesc',), all=False, raw=False, version=u'2.26'):
AttributeError