I had the exact same problem which got progressively worse with time. The only way I could sometimes get it into 1st was to put it in 2nd then slam it up hard into 1st. Finally the dealler had the gearbox replaced under warranty at 32,000 km. (I'm Australian) I was told that there had been 2 gearboxes previously replaced in Australia.
The bad news is that 2 years later and now 64,000 km and out of warranty it appears to be playing up again, although not yet nearly as bad as previously.
Hopefully somebody can diagnose the real fault so I wont have to replace the whole gearbox again.