Is there plans for a pure java SAPJCo? I would rather not have to deal with OS specific libraries and I would think it would be better for SAP to not have to keep the different versions up.
JCO is based on SAP's RFC (remote function call) which is based on IBM's CPI-C protocol.
SAP's implementation of the CPI-C stack is written in C language. For windows based systems this is represented by the librfc32.dll. This implementation is heavily used in the SAP R/3 environment. Compared to that its usage by the JAVA Connector is marginal (in SAP's eyes).
So I do not think that SAP will ever develop a new CPI-C implementation in pure JAVA.