bug in coreutils-5.97-23 date program or is tz?

[Joseph Conrad]

# date
Sun Mar 14 18:47:12 MDT 2010

# date -d "01:59 2010-03-14"
Sun Mar 14 01:59:00 MST 2010

# date -d "02:00 2010-03-14"
date: invalid date `02:00 2010-03-14'

# date -d "02:59 2010-03-14"
date: invalid date `02:59 2010-03-14'

# date -d "03:00 2010-03-14"
Sun Mar 14 03:00:00 MDT 2010

# rpm -q tzdata
tzdata-2010e-1.el5

# rpm -q coreutils
coreutils-5.97-23.el5_4.2

# cat /etc/redhat-release
CentOS release 5.4 (Final)