My 02 had a leaky rh shaft seal. I took it to a diff shop after the warranty ran out.
They took the diff apart, and found that the differential carrier and rh output shaft were worn out (no bearing on rh output shaft, just sits in the diff spline).
I phoned up Suzuki, and they gave me goodwill warranty extension for parts only, and they had to do the work.
If anyone has a rh shaft seal leak, I would say it is very highly likely more than just a seal! If you can shake the rh output shaft, you definately have wear.
Marc