RTFM button not displayed in Rt window

Hi all,

rt-3.0.10-3 on redhat ES 3.0 installed using yum
RTFM-2.0.4
mysql-server-3.23.58-1.9
libdbi-dbd-mysql-0.6.5-5
mysql-3.23.58-1.9

RT works fine
RTFM ‘make install’ was ok and all FM_* tables are created in rt
database

But there is no button in RT page to connect to the knowleadgebase .

In RTFM Makefile the following setup was used:
INSTALL = /bin/sh ./install-sh -c
##RT_PREFIX = /opt/rt
RT_PREFIX = /usr/lib/rt

CONFIG_FILE_PATH = $(RT_PREFIX)/etc
CONFIG_FILE = $(CONFIG_FILE_PATH)/RT_Config.pm
RT_LIB_PATH = $(RT_PREFIX)/lib
RT_LEXICON_PATH = $(RT_PREFIX)/local/po
MASON_HTML_PATH = $(RT_PREFIX)/share/html
#RT_SBIN_PATH = $(RT_PREFIX)/sbin/
RT_SBIN_PATH = /usr/sbin/
(Note: I run 2 times the Makefile changing RT_PREFIX:
1st run RT_PREFIX = /var/rt
2nd run RT_PREFIX = /usr/lib/rt (after dropping FM_*
tables)

Any help is appreciated.
Thanks,
Valter