Alarm Problem

I don't want to start up the old debate of whether an alarm is a good thing or a bad thing. I just want a few opinions on what might be causing my slight problem.
I've just fitted an alarm and it all works fine apart from every time I arm it the in-line fuse in the wire that connects into the R/H indicator circuit blows. The indicators work fine otherwise. The fuse as supplied with the alarm is rated 5 amps. It would appear that the R/H indicator circuit is wanting to draw more than 5 amps. Possibly a bad earth on the R/H indicator?
Peoples thoughts would be valued.

[Sid Squid]

A bad earth would lessen the current flow - more resistance.
Check your connections, have you connected the hot from the alarm to the earth of the light? The indicators would still work correctly as the alarm will have a pair of diodes to stop current feeding back through the alarm and firing the other indicator when they're being used normally.
Are the indicators separately earthed? If they are and your connections are reversed the live from the alarm will deck when the alarm flash fires, the bulb obviously can be wired either way, but some indicators earth one line.