strange message running gtags

Hi,
I tried using global and gtags, but receive some messages that make me 
wonder if everything works ok. When I run gtags I get the following:
----------------
[tomek@grzejhost src]$ gtags
Warning: missing namespace block. [+43 
./plugins/sound/arts/sound-arts.cpp](0x80e).
Warning: missing namespace block. [+43 
./plugins/sound/arts/sound-arts.cpp](0x3b).
Warning: missing namespace block. [+43 
./plugins/sound/arts/sound-arts.cpp](0x80e).
Warning: missing namespace block. [+43 
./plugins/sound/arts/sound-arts.cpp](0x3b).
sort: invalid option -- 1
Try `sort --help' for more information.
sort: invalid option -- 1
Try `sort --help' for more information.
sort: invalid option -- 1
Try `sort --help' for more information.
sort: invalid option -- 1
Try `sort --help' for more information.
sort: invalid option -- 1
Try `sort --help' for more information.
....
----------------
and many more of that

Then when I try tu use global I get the same message:

----------------
[tomek@grzejhost src]$ global -x dockapp_create_pixbuf
sort: invalid option -- 1
Try `sort --help' for more information.
----------------

Is the usage of sort somewhere configurable or is this a bug?
Here are program versions if they are important:

----------------
[tomek@grzejhost src]$ global --version
4.7
[tomek@grzejhost src]$ sort --version
sort (coreutils) 5.0
Written by Mike Haertel and Paul Eggert.
----------------

Thanks for help,
Tomek Grzejszczyk