Lpc2000

We're seeing some strange pin behavior between an lpc2106 (on an Olimex
H2106 board) and a USB FIFO (DLPUSB245M).  I'm wondering if anyone has
any ideas.  When running a simple loopback test sending data from lpc to
FIFO, bits 2 and 3 (on P0.02 and P0.03) do not get set to 1 but on the
next byte sent they do (if they would be 1 on that byte).  

Example:  Sending a sequence of 16 bytes (values 0x00-0x0f) whenever bit
2 or 3 transitions from 0 to 1 (i.e. on 0x4, 0x8, 0xc) it is 0 but on
the next byte sent it is 1.  There is no issue with a 0 -> 1 transition.

        hex     bin    actual
Sending 0x00 00000000 00000000
Sending 0x01 00000001 00000001
Sending 0x02 00000010 00000010
Sending 0x03 00000011 00000011
Sending 0x04 00000100 00000000 <- bit 2 is 0, should be 1
Sending 0x05 00000101 00000101 <- bit 2 is 1 this time
Sending 0x06 00000110 00000110
Sending 0x07 00000111 00000111
Sending 0x08 00001000 00000000 <- bit 3 is 0, should be 1
Sending 0x09 00001001 00001001 <- bit 3 is 1 this time
Sending 0x0a 00001010 00001010
Sending 0x0b 00001011 00001011
Sending 0x0c 00001100 00001000 <- bit 2 is 0, should be 1
Sending 0x0d 00001101 00001101 <- bit 2 is 1 this time
Sending 0x0e 00001110 00001110
Sending 0x0f 00001111 00001111

This doesn't happen on any of the other 6 data pins.  We were thinking
it might have something to do with the alternate functions on
P0.02/P0.03 (I2C or timer 0) but we are not using those functions and in
fact are explicitly setting P0.02/P0.03 to GPIO at the beginning of the
program.

Any ideas?

TIA,

Curt