So add it to your code and here it is:

<iframe width="425" height="350" frameborder="0" scrolling="no"
marginheight="0" marginwidth="0" src="http://maps.google.de/maps?
f=q&amp;hl=de&amp;geocode=&amp;q=Von-Tambach-Stra%C3%9Fe+3,+49584+F
%C3%BCrstenau&amp;sll=51.151786,10.415039&amp;sspn=11.943601,39.550781&amp;ie=UTF8&amp;g=Von-
Tambach-Stra%C3%9Fe+3,+49584+F
%C3%BCrstenau&amp;s=AARTsJrLqHJOkxky0QPTRodSEEVRqhTiVw&amp;ll=52.519146,7.668285&amp;spn=0.01828,0.036478
&amp;iwloc=near&amp;z=14&amp;output=embed"></iframe><br><small><a
href="http://maps.google.de/maps?f=q&hl=de&geocode=&q=Von-
Tambach-Stra%C3%9Fe+3,+49584+F
%C3%BCrstenau&amp;sll=51.151786,10.415039&amp;sspn=11.943601,39.550781&amp;ie=UTF8&amp;g=Von-
Tambach-Stra%C3%9Fe+3,+49584+F
%C3%BCrstenau&amp;ll=52.519146,7.668285&amp;spn=0.01828,0.036478&amp;z=14&amp;source=embed"
style="color:#0000FF;text-align:left">Größere Kartenansicht</a></
small>

And here is a website of my goolepages with this iframe:
http://geissler.hoenow.googlepages.com/embeddedmap3

Please NOTE:

I added the iwloc parameter in the embedding code of my googlepage
website only in that first part for the iframe of the SMALL map.
This is intended in order to show you:
if you click the link below the map "Größere Kartenansicht"
(BTW: I created the embedded map from my German GoogleMaps)
You will get the LARGE map with the OPENED infow window - just to
clarify & demonstrate the matter.

http://groups.google.com/group/Google-Maps-Troubleshooting/browse_thread/thread/318dc76597872f2e

Remove the info / address pop up on a google map embed code.

Until last month: the iwloc parameter was responsible to GET the
window opened or not the following way:
It the parameter was missing by deafult the infow window was NOT
opened.
And vice versa: to get it opened the parameter should there OR while
the gotten code wouldn't  be contain the iwloc ONE was forced to ADD
it manually!

I did not notice WHEN they changed this!!!
However NOW it seems to be reverse:
In your case (in your provided embedding code [maybe created using my
previous hints in this thread]) the iwloc parameter WAS NOT THEREIN.
I confirm: NOW this means obviously the info window will OPENED by
DEFAULT.

To get the embedding code for an iframe with an UN-opened Placemark
it's again necessary to ADD an OTHER value for the IWLOC paramter:
iwloc=near DOES the trick NOW!

Removing info / address bubble from google maps embed code

google, code

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