I want to connect my bspeech Bluetooth headset to my office phone
(corded phone, land line and not bluetooth-enabled) to receive and
make phone calls via the bluetooth headset. The phone is equipped with
a corded headset from Plantronics, so the device/adaptor I am looking
for should use the RJ-jack the plantronics headset is currently
connected to (the phone handset).

So far I have found the Jabra A200 and 210 witch can be used with
jabra bt headsets only and the LG U8110 - U8120 Bluetooth Conversion
Adaptor with seem to be compatible with any bt headset - but I was not
able to confirm if it can be used to replace a regular phone handset.

Please include a online shop link where I can order (delivery to
germany would be good) and list necessary parts (like an adaptor for
an 2,5 mm jack to RJ)

Thank You!

P.S.: By the way: Is it such a unusual questions? I mean there are
millions of people using corded headsets AND owning Bluetooth headsets
(for their mobile phones only) - why not "cutting the cord" in the
office the easy way (apart from buying expensive GN netcom products)?
A market is here!

I was unable to determine if the LG U8110 - U8120 Bluetooth Conversion
Adaptor can be hooked up to a non-LG phone handset, webpage tells it
is for "any regular LG phone". I have a normal analag phone (not
ISDN).

Just wanted to make sure you're aware that gens-ga, who posted a
comment on your previous question, is not a Google Answers Researcher,
and cannot post an official answer to your question nor receive
compensation.

Hello pinkfreud-ga,
thank you for clarification - I was happy that someone finally seemed
to have an answer that I didnt bother really. How can I check that
someone is a researcher here?

And still no solution... so sad.

I checked out a DECT headset in the meantime its not bluetooth and I
cannot use it with corded office phone, just with dect cord-free ones.

As I can see, you have two options, 1) get a bluetooth 'audio gateway'
like: http://www.maplin.co.uk/Module.aspx?ModuleNo=45563&doy=6m8&C=SEO&U=Template

or 2) to get a bluetooth USB adaptor to plug into your work computer
and use skypeout (http://www.skype.com/products/skypeout/) to
make/receive telephone calls, which is the cheapest solution all
round, assuming your network administrator is ok with it.  Skype
doesn't add much network overhead, but you should ask the person in
charge of the network anyway.