求助！安装gaim提示缺少GTK2.0

安装gaim提示缺少GTK2.0,下载了Gtk2.4.1 安装，按说明书上：
./configure --prefix=/opt/gtk
出现错误如下:
library requirements not met ,consider adjusting the pkg_config_path,environment variable .if you libraries are in nostandard prefix, so pkg_config can find them.