checkbutton does not notice "text filled into gtk_entry" and stays passive

[Daniel Hops <Daniel Hops eed ericsson se>]

Hello,

I have a question:
my programm has a lot of checkbuttons_with_labels. Most of them are
packed using a table layout. Some of them are packed into a hbox, which
is gtk_table_attached into the layout. These checkbuttons have 3
corresponding fields: from_date, separator '-' and to_date. When text is
insert into the from/to-date entries the checkbutton does not notice it
and stays passive and the user has to make an extra click on it.
The rest of the checkbuttons with only one corresponding label_entry
gets activated when text is filled in the entry.
What can I do to enable the date-from-to checkbuttons to get activated
automatically?

PS: I am using gtk+1.2.3 and C

Regards
Daniel Hops

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