Hi Praveen
Yes, OAuth is a challenging part especially if it is not natively supported by the adapter.
Although the blog mentioned that OAuth is planned to be shipped with SP10, it is not mentioned anywhere in the below release notes for SP10.
SAP Process Integration - What's New in SAP NetWeaver 7.4 (Release Notes) - SAP Library
Since you have asked Alex directly in his blog, maybe you can wait for his reply on the OAuth feature.
If OAuth is not out yet, I think it might also be hard to develop a workaround solution - even if you can perform a step to get the OAuth token, custom HTTP headers are also not supported yet, so you can't put the OAuth token value into the HTTP request.
Rgds
Eng Swee