Lpc2000

Hi am new to this forum.I am using "free" KEIL evalution software as 
my IDE to work on LPCE2214 OLIMEX board. Am able to work on TIMER and 
serial port in "polling" mode. But when I enable ISR functions using 
VIC,my program in not jumping to ISR.but in debug mode i could see 
the jump to ISR. also I have DefaultISR in my code.here am attaching 
my code with this mail.
// This program is created for LPC-E2214 board
#include "lpc22xx.h"

#define OSCILLATOR_CLOCK_FREQUENCY 14745600 //in MHz
#define PLOCK 0x400 //in MHz


void Initialize(void);
void feed(void);
void UART0Initialize(unsigned int baud);
void UART0WriteChar(unsigned char ch0);
unsigned char UART0ReadChar(void);
unsigned char UART0ReadChar_nostop(void);
unsigned int processorClockFrequency(void);
unsigned int peripheralClockFrequency(void);

void tc0(void)__irq;
static void DefDummyInterrupt(void)__irq;

void init_timer(void);
void InitVIC(void);

long volatile timeval;

void wait (void) /* wait function */
{
unsigned long i;
i = timeval;
while ((i + 10) != timeval); /* wait 100ms */
}



int main()
{
/**** VARIABLES ****/
unsigned char ch0 = 0x0;
unsigned char ch1 = 0x0;
long i=0;

/**** INITIALIZATION ****/
// Frequency initialization
Initialize();
// UART initialization
UART0Initialize(9600);

init_timer();
InitVIC();


while(1)
{

UART0WriteChar('3');
wait();

UART0WriteChar('2');
wait();
}

}


void Initialize(void)
{

// Setting Multiplier and Divider values
PLLCFG=0x23;
feed();

// Enabling the PLL */
PLLCON=0x1;
feed();

// Wait for the PLL to lock to set frequency
while(!(PLLSTAT & PLOCK)) ;

// Connect the PLL as the clock source
PLLCON=0x3;
feed();

// Enabling MAM and setting number of clocks used for Flash memory 
fetch (4 cclks in this case)
MAMCR=0x2;
MAMTIM=0x4;

// Setting peripheral Clock (pclk) to System Clock (cclk)
VPBDIV=0x1;

}


void feed(void)
{
PLLFEED=0xAA;
PLLFEED=0x55;
}

/* Setup the Timer Counter 0 Interrupt */
void init_timer (void) {
T0MR0 = 149999; // 10mSec = 150000-1 counts
T0MCR = 3; // Interrupt and Reset on MR0
T0TCR = 1; // Timer0 Enable
VICVectAddr0 = (unsigned long)tc0; // set interrupt vector in 0
VICVectCntl0 = 0x20 | 4; // use it for Timer 0 Interrupt
VICIntEnable = 0x00000010; // Enable Timer0 Interrupt // Timer0 Enable
}

/* Timer0 Compare-Match Interrupt Handler (ISR) */
/* Timer Counter 0 Interrupt executes each 10ms @ 60 MHz CPU Clock */
/* Timer Counter 0 Interrupt executes each 10ms @ 60 MHz CPU Clock */
void tc0 (void) __irq
{
++timeval;
T0IR = 1; // Clear interrupt flag
VICVectAddr = 0; // Acknowledge Interrupt
}
void DefDummyInterrupt(void)__irq
{
;
}
void InitVIC()
{
VICDefVectAddr = (unsigned long)DefDummyInterrupt;
}


/**** UART0 ****/
void UART0Initialize(unsigned int baud)
{
unsigned int divisor = peripheralClockFrequency() / (16 * baud);

U0LCR = 0x83;


//devisor
U0DLL = divisor & 0xFF;
U0DLM = (divisor >> 8) & 0xFF;
U0LCR &= ~0x80;

//set functionalite to pins: port0.0 -> TX0, port0.1 -> RXD0
PINSEL0 = PINSEL0 & ~0xF | 0x5;
}

void UART0WriteChar(unsigned char ch0)
{
//when U0LSR_bit.THRE is 0 - U0THR contains valid data.
while ((U0LSR && 0x20) == 0);
U0THR = ch0;
}

unsigned char UART0ReadChar(void)
{
//when U0LSR_bit.DR is 1 - U0RBR contains valid data
while ((U0LSR && 0x01) == 0);
return U0RBR;
}
unsigned int processorClockFrequency(void)
{
//return real processor clock speed
return OSCILLATOR_CLOCK_FREQUENCY * (PLLCON & 1 ? (PLLCFG & 0xF) + 
1 : 1);
}

unsigned int peripheralClockFrequency(void)
{
//VPBDIV - determines the relationship between the processor clock 
(cclk)
//and the clock used by peripheral devices (pclk).
unsigned int divider;
switch (VPBDIV & 3)
{
case 0: divider = 4; break;
case 1: divider = 1; break;
case 2: divider = 2; break;
}
return processorClockFrequency() / divider;
}

Please look into this and It would be a great help for me as i have 
been trying for it from past 2 weeks.
I think, abviously iam missing some things. I did not changed any 
things in startup.s file.I will post the start up code if any body 
wanted to look in
please guide me.appreciate your help.

Thanks