更新源代码出现如下错误

玄鹤

Parsing supfile "/etc/stable-supfile"
Connecting to cvsup3.cn.FreeBSD.org
Connected to cvsup3.cn.FreeBSD.org
Server software version: SNAP_16_1h
Negotiating file attribute support
Exchanging collection information
Establishing multiplexed-mode data connection
Running
Updating collection src-all/cvs
Server warning: RCS file error in "/usr/local/etc/cvsup/prefixes/FreeBSD.cvs/src/release/picobsd/build/mfs.mtree,v": 1: "head" expected
Shutting down connection to server

好像是本地文件的错误，请教如何解决？谢谢了！！