arch_printf() formatting

Hi,
I'm trying to debug via UART,
i followed the FAQ athttp://support.dialog-semiconductor。com/faq/how-debug-uart
and it works when I print a string like
arch_printf("\Test\r\n");

but when i try to print a variable :
int16 tmr0;
...
...
tmr0=10001;
arch_printf("%Lx",tmr0);
....

i receive following error in terminal window:
FATAL: unsupporte

Can you please help me with correct formatting?
Thanks!