BEX and ITS

We are currently connecting to BW through an ITS Server running Linux. Transaction rrmx complains that we need to install the correct version of excel to run this transaction. It also puts out a BRAIN870 message. I have a feeling that this will not work due to the fact that it is trying to use some type of excel which do not exist on a Linux Server. Is this the correct assumption? I have no problem with a standard sapgui connection but unfortunately, the company wants to web enable everthing. Any ideas? Is Web BEX the only solution? Please let me know.