Two hosters - redirect url from one to the other

[vistree]

Hi, I have a small problem here with redirect.
There are two domains at two different hosters.
domain1.com is at hoster1
domain2.com is at hoster2
Both have no DNS-setup and I don't have a root-access

Now I want to set up a CMS in one of the packages, say at hoster1. This CMS is multidomain usable.
Therefore I want to redirect domain2.com to domain1.com WITH the URL (domain2.com) kept.

Is there a way for this? And how is the "reaction" of google of the possible solutions?

Kind regards