You will get to see the listing as shown in the image below, if you have chosen to default installation of RSA v8.0
Starting with v8.0, the Rational Software Architect product has decided to bundle the driver support ( Informix v11.xx is part of it ) as a separate add-on, which needs to be chosen ( selecting the check box ) during the installation process of RSA v8.0
The following image provides you a snap shot of the RSA v8.0 installation window. Navigate to the check box, as shown and enable it, to have the v11.xx support on RSA v8.0
Choose IBM Rational Software Architect --> Code Development and Quality Tools --> Data Tools
Once the said option is chosen, complete the installation. Open up the RSA v8.0 application and choose to create 'New Profile'. Now, you get to see the support for Informix JDBC driver and IBM Data Server Driver for JDBC and SQLJ for the versions IDS v11.10 and IDS v11.50 listed in the drop down menu.
The following image depicts the same
In case of issues / queries, please reach out to me