Pango problems with GtkCellRenderText

[Will Luesley <lists luesley com>]

I've got a GtkTreeList with one of the columns rendinging strings with a 
GtkCellRendererText (which is also editable).

I'm presenting a sequence of bytes as characters in the format
xx-xx-xx-xx

The problem I've got is that Pango thinks that there is something 
special about a string with hyphens in, and attempts to render it in 
many weird and wonderful ways. Some sequences e.g. 01-01-01-01 come out 
with characters that look like mini matrices, while others such as 
ff-ff-ff-ff produce the following warning on the command line
Pango-WARNING **: Invalid UTF-8 string passed to pango_layout_set_text()

  Is there a way of stopping this? I know with a GtkLabel you can 
enable and disable Pango markup - can I do the same here.



Regards,

Will.