Now, we got iPhone SDK beta 5, and we got lots of warning code based on SDK 2.0

step 1,
        in ur appname_Prefix.pch add a line
        
        #define TARGET_IPHONE_VERSION 3

step 2,
        anywhere you get warring, add :
        
#if TARGET_IPHONE_VERSION > 2
        //code for 3.0
#else
        //code for 2.0
#endif

enjoy your no warning compiler