Yes, Rational Developer for Power Systems Software (RDp) is a compatible IDE for iSeries (IBM i, System i) development, and works hand-in-hand with Rational Team Concert for Power Systems Software (RTCp).

More on RDp: http://www-01.ibm.com/software/rational/products/rdp/
More on RTCp: http://jazz.net/projects/rational-team-concert-power/

Is it possible to connect to an iSeries development platform in RTC ?
If yes - which ?
If No - are there any plans for any ?