So, you've followed the Gentoo Linux Localization Guide and the the NTP guide on the wiki...
cp /usr/share/zoneinfo/Europe/London /etc/localtime
In /etc/conf.d/clock:
TIMEZONE="Europe/London"
In /etc/conf.d/clock:
CLOCK="UTC" CLOCK_SYSTOHC="yes"
In /etc/ntp.conf:
# Some UK based stratum 2 servers server ntp2b.mcc.ac.uk iburst server ntp2c.mcc.ac.uk iburst server ntp2d.mcc.ac.uk iburst server ntp.cis.strath.ac.uk iburst
/etc/init.d/ntpd restart
...but the time is still not adjusted for daylight savings. Perhaps you're getting an error like this in /var/log/messages:
time correction of -3501 seconds exceeds sanity limit (1000); set clock manually to the correct UTC time.
The (blindingly obvious) solution... Set the clock manually to the correct UTC time!
ntpdate pool.ntp.org /etc/init.d/ntpd restart
