I am unable to compile Zabbix 1.8.1 on CentOS 5.4 with SSH support. Please see errors below...

My configure line...

./configure \
--with-ssh2 \
--with-openipmi \
--with-jabber \
--with-mysql \
--with-libcurl \
--enable-server \
--enable-proxy \
--enable-agent \
--with-net-snmp \

Compile error...

gcc -DHAVE_CONFIG_H -I. -I../../../include -O2 -g -m64 -mtune=generic -I/usr/include/mysql -g -pipe -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m64 -D_GNU_SOURCE -D_FILE_OFFSET_BITS=64 -D_LARGEFILE_SOURCE -fno-strict-aliasing -fwrapv -I/usr/include/rpm -I/usr/local/include -I/usr/include/gdbm -I/usr/lib64/perl5/5.8.8/x86_64-linux-thread-multi/CORE -I. -I/usr/include/net-snmp -Iusr/include -I/usr/include -MT checks_ssh.o -MD -MP -MF .deps/checks_ssh.Tpo -c -o checks_ssh.o checks_ssh.c
checks_ssh.c: In function 'waitsocket':
checks_ssh.c:64: error: 'LIBSSH2_SESSION_BLOCK_INBOUND' undeclared (first use in this function)
checks_ssh.c:64: error: (Each undeclared identifier is reported only once
checks_ssh.c:64: error: for each function it appears in.)
checks_ssh.c:67: error: 'LIBSSH2_SESSION_BLOCK_OUTBOUND' undeclared (first use in this function)
make[3]: *** [checks_ssh.o] Error 1
make[3]: Leaving directory `/usr/src/redhat/BUILD/zabbix-1.8.1/src/zabbix_server/poller'
make[2]: *** [all-recursive] Error 1
make[2]: Leaving directory `/usr/src/redhat/BUILD/zabbix-1.8.1/src/zabbix_server'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/usr/src/redhat/BUILD/zabbix-1.8.1/src'
make: *** [all-recursive] Error 1