SVN access

[lists ir compulink co uk]

I'm running meld 1.0.0 on Redhat Enterprise Linux 3.

When within a CSV or SVN working directory if I run meld . meld fails to start with the window showing:

Traceback (most recent call last):
File "/usr/share/meld/meld", line 100, in ?
meldapp.main()
File "/usr/share/meld/meldapp.py", line 866, in main
app.append_cvsview( [a] )
File "/usr/share/meld/meldapp.py", line 756, in append_cvsview
doc = cvsview.CvsView(self.prefs)
File "/usr/share/meld/cvsview.py", line 388, in _init_
self.treeview_column_location.set_visible( self.button_flatten.get_active() )
AttributeError: 'gtk.Label' object has no attribute 'get_active'

I've no doubt this is some set up problem as I've used meld on other machines fine, but I'm stumped.
Is there some test I could try or place I could look? 

Chris