Is the configuration in startup.s file generated using KEIL IDE directly putting the Fcpu @ 60 MHz?
Do you still have this problem? 

This can be set both in the startup.s file and in main code section.

It is up to you to decide which one to use.

In the startup.s file, 


navigate to Configuration Wizard
Click PLL Setup
Set PLL Multiplier to 0x03


In the main section of your program, you may obtain the code for setting the clock to 60Mhz from the LPC2119 docs.