Expression lost if new text added from first charachter after first calcuation

Binary package hint: gcalctool

Perform a calculation, for example:
"1000/5"
Result window shows:
"200"
Now take the inverse of the result, Press the 'home' key or use mouse to move cursor to the left of '2' character and enter "1/"
Expression becomes "1/" instead of "1/200"

New text can be inserted anywhere in the result expression except for to the left of the result.

ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: gcalctool 5.32.0-0ubuntu4
ProcVersionSignature: Ubuntu 2.6.35-28.49-generic 2.6.35.11
Uname: Linux 2.6.35-28-generic x86_64
NonfreeKernelModules: nvidia
Architecture: amd64
Date: Sat Apr 9 14:05:23 2011
EcryptfsInUse: Yes
ExecutablePath: /usr/bin/gcalctool
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release amd64 (20100429)
ProcEnviron:
 PATH=(custom, user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: gcalctool
XsessionErrors:
 (gnome-power-manager:1959): Gtk-WARNING **: A floating object was finalized. This means that someone
 (polkit-gnome-authentication-agent-1:1997): GLib-CRITICAL **: g_once_init_leave: assertion `initialization_value != 0' failed
 (nautilus:1989): GConf-CRITICAL **: gconf_value_free: assertion `value != NULL' failed
 (process:2268): Gtk-WARNING **: Locale not supported by C library.
 (process:2462): Gtk-CRITICAL **: set_table: assertion `buffer->tag_table == NULL' failed