freeradius-1.0.5 compilation error (library -lz not found)

[K Pang]

Hi All,
Happy New Year to all of you!
i encounterd some compilation errors when compiling freeradius-1.0.5 on 
solaris 8. below is the errors.

/usr/local/src/freeradius-1.0.5-pi/libtool --mode=link gcc -release 1.0.5 \
-module -export-dynamic  -g -O2 -D_REENTRANT -D_POSIX_PTHREAD_SEMANTICS 
-DOPENSSL_NO_KRB5 -I/usr/local/ssl/include -Wall -D_GNU_SOURCE -g -Wshadow 
-Wpointer-arith -Wcast-qual -Wcast-align -Wwrite-strings -Wstrict-prototypes 
-Wmissing-prototypes -Wmissing-declarations -Wnested-externs -W 
-Wredundant-decls -Wundef  -I../.. -I../../../../include \
-I/usr/local/mysql/include -I/usr/local/src/freeradius-1.0.5-pi/libltdl -o 
rlm_sql_mysql.la -rpath /usr/local/radius5/lib sql_mysql.lo 
-L/usr/local/mysql/lib/mysql -lmysqlclient -lnsl -lresolv -lsocket -lposix4  
-lpthread -lz -lnsl -lresolv -lsocket -lposix4  -lpthread -lz
rm -fr .libs/rlm_sql_mysql.la .libs/rlm_sql_mysql.* 
.libs/rlm_sql_mysql-1.0.5.*
/usr/ccs/bin/ld -G -h rlm_sql_mysql-1.0.5.so -o .libs/rlm_sql_mysql-1.0.5.so 
  sql_mysql.lo  -R/usr/local/mysql/lib/mysql -R/usr/local/mysql/lib/mysql  
-L/usr/local/BerkeleyDB.4.2 -L/usr/local/mysql/lib/mysql 
/usr/local/mysql/lib/mysql/libmysqlclient.so -lnsl -lresolv -lsocket 
-lposix4 -lpthread -lz -lnsl -lresolv -lsocket -lposix4 -lpthread -lz -lc
ld: fatal: library -lz: not found
ld: fatal: library -lz: not found
ld: fatal: File processing errors. No output written to 
.libs/rlm_sql_mysql-1.0.5.so
make[10]: *** [rlm_sql_mysql.la] Error 1
make[10]: Leaving directory 
`/usr/local/src/freeradius-1.0.5-pi/src/modules/rlm_sql/drivers/rlm_sql_mysql'

what's 'library -lz not found'? i've no idea what's this library.
is it caused by missing of certain packages? if so, which package should i 
install? pls advise.
thanks in advance!


Rgds,
Pang