Cursor appears twice

[Ratcliff]

This may be a 'feature' but I have a client using Word who keeps
having a problem with the cursor appearing in two places. When he
clicks to enter the insertion point, he sees that cursor AND another
cursor in a different place. As far as I can tell, that 'other' place
is wherever the insertion point was previously.

If this is some editing feature, can someone tell me how to turn it
off. Has anyone else experienced this? He's using Word 2002 on XP.

Thanks in advance
P Ratcliff