iPhone 4 no longer detects SIM card, how can I fix it? Since 3 months I do have an iPhone 4, 3 weeks ago i started to get no SIM card installed error increasingly more frequent. Right now the phone is unusable. I went to a sales office of my mobile supplier, they tried a different sim card. But this did not solve the issue unfortunately. 

They want it now for reparation, which means i loose my iphone for 2 or 3 weeks. Are there any other possibilities, on the internet I read a few sites which speak about sticky tape or applying some glue to the simcard slider. But I don't want to run the risk of losing my warranty and ruining the iphone's interior.

I have the feeling that the problem is only at the slider, so I'm a kind of dissatisfied with the iphone being taken in 2 weeks for service.
Are there any other options?
Take it to the Apple store if there is one near you. Usually they will switch out the phone if still under warranty.