Hello,
Are you still working on this? I´m having issues with the source code, I mean, it compiles normally using LPCXpresso, I flash it using Flash Magic but it does not work, I don´t know why... I can send you the source files and also the .HEX so you can test on your board, and help me if you want...
I wrote my own code based on code I had previously written for ATMEGA and PIC. It looks for the line break using bit 4 of U0LSR, which resets a counter. The next 513 bytes it receives are put in a buffer using the counter as a pointer.
Then it's simple enough to find the data required by loading byte n+1 from the buffer. I have subsequently rewritten it for LPC8xx/LPC15xx which have the same UART but which is different from the LPC11xx/LPC13xx UART.