Google indexing incorrect urls

Just been looking at the stats on the sites in particular the pages that google is looking at



Clicking on any link that the stats that google is showing as visited gives a broken URL such as

[url]http://109.203.99.180/~watercoo/~watercoo/index.php?dispatch=products.view&product_id=29818[/url]



But it should be

[url]http://109.203.99.180/~watercoo/index.php?dispatch=products.view&product_id=29818[/url]



Its shortened the url but its going to 109.203.99.180/~watercoo/~watercoo/xxxxxxxxxx (one to many /~watercoo/



This happens on ANY date that you select for googlebot.



As this is quite serious where the heck can I start to look to fix this?



update this is showing for any bot thats hit the site.