Some Buttons in the Mapping module don't work on IE 7.0.5730.13 & IE 6.0

[Tim McNamara]

See http://trac.sahanapy.org/ticket/91

Environment/Machine configuration:
IE Version - 7.0.5730.13
Windows XP version - 2002 Service Pack 3
Machine configuration:
Pentium(R) 4, CPU 2.60GHz
2.59 GHz, 0.99GB of RAM
Prerequisites:
User should be logged in to the system.
(User must use IE 7.0.5730.13 or IE 6.0)
Steps:
1) Click ‘Mapping’.
2) Click ‘Map Service Catalogue’.
3) Click ‘Defaults’.
Expected Result:
The respective page should load.
Actual Result:
Clicking the button results nothing.
Note:
All the buttons in this page have this issue (regarding IE 7.0.5730.13 & IE 6.0) but these work properly on Firefox 3.5.3.