Problem: cursor jumps to right side of window in text editor

[Barry Kauler <bkauler goosee com>]

Hi guys, I've just joined the list.
I'm the main developer of Puppy Linux, a tiny 60M live-CD.
Puppy has been happily using GTK 2.2 for the last year or
so -- the binaries pulled off Mandrake 9.2.

Now I want to upgrade. Have been experimenting with GTK 2.4.0
and also 2.6.1. The former I got out of Vector Linux 5.0STD,
as that is my new compile host. GTK 2.6.1 I compiled myself
(as well as glib, pango and atk).

Okay, the upgrades work in Puppy, except for one upsetting
problem. When I start Leafpad or TEA text editors, regardless
of whether they were compiled under GTK 2.2, 2.4 or 2.6, get
the same bug --
Open new file, cursor appears at right side of window.
Type numerical digits, like "123", cursor and digits stay on
right side, until create a new line -- if cursor is on another 
line, then "123" displays on left side where it should be, but
move cursor back to the "123" line and it jumps over to the
right side.

If I type any alphabetic character, the line immediately jumps
to the left side.

This behaviour is not appropriate for a text editor!
Anyone know how to turn it off?
Obviously some configuration setting somewhere...

Regards,
Barry Kauler
http://www.goosee.com/puppy