Has Google problems in indexing pages that use <base href=""> the last days?

[SimCaffe]

Since a couple of days I have the problem, that Google Webmaster tools are showing a lot more 404 Errors than normal. If I go thru the list I find very strange URLs that look like two paths put together. For example:

http://www.domain.de/languages/languageschools/havanna/languages/languageschools/london/london.htm

If I check on which page Google found that path it is showing me the following URL:

http://www.domain.de/languages/languageschools/havanna/spanishcourse.htm

If I check the source code of the Page for the Link leading to the London Page it looks like the following:

[...](languages/languageschools/london/london.htm)

So to me it looks like Google is ignoring the <base href="..."> and putting the path together as following:

Part 1) http://www.domain.de/laguages/languageschools/havanna/ instead of base href

Part 2) languages/languageschools/london/london.htm

Result is the wrong path! http://www.domain.de/languages/languageschools/havanna/languages/languageschools/london/london.htm

I know finding a solution is not difficult, I can use absolute paths instead of relative ones. But:

-          Does anyone make the same experience?

-          Do you know other reasons which could cause such a problem?

P.s.: I am quite sure that the CMS (Typo3) is not generating these paths randomly. I would like to be sure before we change the CMS's Settings to absolute paths!