Something

ld /usr/lib/lighttpd/mod_sql_vhost_core.so 
ld: warning: cannot find entry symbol _start; not setting start address
/usr/lib/lighttpd/mod_sql_vhost_core.so: undefined reference to `buffer_init'
/usr/lib/lighttpd/mod_sql_vhost_core.so: undefined reference to `stat_cache_get_entry'
/usr/lib/lighttpd/mod_sql_vhost_core.so: undefined reference to `config_insert_values_global'
/usr/lib/lighttpd/mod_sql_vhost_core.so: undefined reference to `buffer_copy_string_buffer'
/usr/lib/lighttpd/mod_sql_vhost_core.so: undefined reference to `config_check_cond'
/usr/lib/lighttpd/mod_sql_vhost_core.so: undefined reference to `buffer_init_string'
/usr/lib/lighttpd/mod_sql_vhost_core.so: undefined reference to `buffer_free'
/usr/lib/lighttpd/mod_sql_vhost_core.so: undefined reference to `log_error_write'

ld /usr/lib/lighttpd/mod_postgresql_vhost.so 
ld: warning: cannot find entry symbol _start; not setting start address
/usr/lib/lighttpd/mod_postgresql_vhost.so: undefined reference to `buffer_init'
/usr/lib/lighttpd/mod_postgresql_vhost.so: undefined reference to `plugin_get_config'
/usr/lib/lighttpd/mod_postgresql_vhost.so: undefined reference to `array_insert_unique'
/usr/lib/lighttpd/mod_postgresql_vhost.so: undefined reference to `buffer_copy_string'
/usr/lib/lighttpd/mod_postgresql_vhost.so: undefined reference to `buffer_copy_string_buffer'
/usr/lib/lighttpd/mod_postgresql_vhost.so: undefined reference to `buffer_is_empty'
/usr/lib/lighttpd/mod_postgresql_vhost.so: undefined reference to `buffer_init_string'
/usr/lib/lighttpd/mod_postgresql_vhost.so: undefined reference to `buffer_free'
/usr/lib/lighttpd/mod_postgresql_vhost.so: undefined reference to `log_error_write'
/usr/lib/lighttpd/mod_postgresql_vhost.so: undefined reference to `data_string_init'