Had leaky oil seals at different parts on 3 of my cars; wira, BLM and honda. All 3 were solved by using rubber restorer called ATP AT-205 Re-Seal. INM, now it has been bought over by Lubegard and renamed to Seal Fixx.

Using it was simple, just mix a capful (estimated) of it into the PSF/ATF reservoir, and let the rubber restorer work its magic for a few days. If it is still weeping a little, add half a cap more.

On BLM and Wira, it was the seals at PS pump that began leak. On honda, it was the PS hose crimps, well known to fail with age.