Description of problem:
rhn-satellite-exporter always fails when satellite-sync using parameter --no-rpms and rhn-satellite-exporter using without --no-rpms.

Version-Release number of selected component (if applicable):
spacewalk-backend-tools-1.2.13-52.el5sat

How reproducible: Always

Steps to Reproduce:
1. satellite-sync --channel <CHANNEL> --no-errata --no-kickstarts --no-rpms
2. rhn-satellite-exporter --channel <CHANNEL> --dir <DIR>
  
Actual results --LOG--:
02:56:19 Exporting short packages...
           ____________________
Exporting: #################### - Done!


02:56:46 Exporting binary RPMs...
           ____________________
Exporting: 02:56:46 
AttributeError caught in dump_rpms.

exit code is 255 

Expected results:

Additional info:
I debug this traceback (/usr/share/rhn/satellite_tools/disk_dumper/iss.py - I just edit ):

Debug: print rpm >> [{'path': None, 'id': 1507}] 

Traceback (most recent call last): 
  File "/usr/share/rhn/satellite_tools/disk_dumper/iss.py", line 848, in dump_rpms 
    satellite_path = os.path.join(CFG.MOUNT_POINT, rpm['path']) 
  File "/usr/lib64/python2.4/posixpath.py", line 60, in join 
    if b.startswith('/'): 
AttributeError: 'NoneType' object has no attribute 'startswith'