While using XDMCP to login from my desktop to my server
(note: running workrave locally works fine, record plugin installed and everything)

kees-jan@fuzzy ~
$ sudo apt-get install workrave
Password:
Reading package lists... Done
Building dependency tree... Done
The following extra packages will be installed:
  libgconfmm-2.6-1c2 libglademm-2.4-1c2a libgnet2.0-0 libgnome-vfsmm-2.6-1c2a
  libgnomecanvasmm-2.6-1c2a libgnomemm-2.6-1c2 libgnomeuimm-2.6-1c2a
The following NEW packages will be installed:
  libgconfmm-2.6-1c2 libglademm-2.4-1c2a libgnet2.0-0 libgnome-vfsmm-2.6-1c2a
  libgnomecanvasmm-2.6-1c2a libgnomemm-2.6-1c2 libgnomeuimm-2.6-1c2a workrave
0 upgraded, 8 newly installed, 0 to remove and 0 not upgraded.
Need to get 1206kB of archives.
After unpacking 3621kB of additional disk space will be used.
Do you want to continue [Y/n]? y
Get:1 ftp://ftp.nl.debian.org etch/main libgconfmm-2.6-1c2 2.14.2-1 [31.2kB]
Get:2 ftp://ftp.nl.debian.org etch/main libglademm-2.4-1c2a 2.6.2-2 [21.8kB]
Get:3 ftp://ftp.nl.debian.org etch/main libgnet2.0-0 2.0.7-1 [111kB]
Get:4 ftp://ftp.nl.debian.org etch/main libgnome-vfsmm-2.6-1c2a 2.14.0-1 [72.3kB]
Get:5 ftp://ftp.nl.debian.org etch/main libgnomecanvasmm-2.6-1c2a 2.14.0-1 [80.7kB]
Get:6 ftp://ftp.nl.debian.org etch/main libgnomemm-2.6-1c2 2.14.0-1 [15.9kB]
Get:7 ftp://ftp.nl.debian.org etch/main libgnomeuimm-2.6-1c2a 2.14.0-1 [127kB]
Get:8 ftp://ftp.nl.debian.org etch/main workrave 1.8.3-1 [746kB]
Fetched 1206kB in 4s (267kB/s)
Selecting previously deselected package libgconfmm-2.6-1c2.
(Reading database ... 96799 files and directories currently installed.)
Unpacking libgconfmm-2.6-1c2 (from .../libgconfmm-2.6-1c2_2.14.2-1_i386.deb) ...Selecting previously deselected package libglademm-2.4-1c2a.
Unpacking libglademm-2.4-1c2a (from .../libglademm-2.4-1c2a_2.6.2-2_i386.deb) ...
Selecting previously deselected package libgnet2.0-0.
Unpacking libgnet2.0-0 (from .../libgnet2.0-0_2.0.7-1_i386.deb) ...
Selecting previously deselected package libgnome-vfsmm-2.6-1c2a.
Unpacking libgnome-vfsmm-2.6-1c2a (from .../libgnome-vfsmm-2.6-1c2a_2.14.0-1_i386.deb) ...
Selecting previously deselected package libgnomecanvasmm-2.6-1c2a.
Unpacking libgnomecanvasmm-2.6-1c2a (from .../libgnomecanvasmm-2.6-1c2a_2.14.0-1_i386.deb) ...
Selecting previously deselected package libgnomemm-2.6-1c2.
Unpacking libgnomemm-2.6-1c2 (from .../libgnomemm-2.6-1c2_2.14.0-1_i386.deb) ...Selecting previously deselected package libgnomeuimm-2.6-1c2a.
Unpacking libgnomeuimm-2.6-1c2a (from .../libgnomeuimm-2.6-1c2a_2.14.0-1_i386.deb) ...
Selecting previously deselected package workrave.
Unpacking workrave (from .../workrave_1.8.3-1_i386.deb) ...
Setting up libgconfmm-2.6-1c2 (2.14.2-1) ...

Setting up libglademm-2.4-1c2a (2.6.2-2) ...

Setting up libgnet2.0-0 (2.0.7-1) ...

Setting up libgnome-vfsmm-2.6-1c2a (2.14.0-1) ...

Setting up libgnomecanvasmm-2.6-1c2a (2.14.0-1) ...

Setting up libgnomemm-2.6-1c2 (2.14.0-1) ...

Setting up libgnomeuimm-2.6-1c2a (2.14.0-1) ...

Setting up workrave (1.8.3-1) ...

kees-jan@fuzzy ~
$ workrave &
[2] 7262

kees-jan@fuzzy ~
$ X Error of failed request:  BadAccess (attempt to access private resource denied)
  Major opcode of failed request:  148 (MIT-SHM)
  Minor opcode of failed request:  1 (X_ShmAttach)
  Serial number of failed request:  162
  Current serial number in output stream:  163
The program 'workrave' received an X Window System error.
This probably reflects a bug in the program.
The error was 'BadShmSeg (invalid shared segment parameter)'.
  (Details: serial 164 error_code 170 request_code 148 minor_code 5)
  (Note to programmers: normally, X errors are reported asynchronously;
   that is, you will receive the error a while after causing it.
   To debug your program, run it with the --sync command line
   option to change this behavior. You can then get a meaningful
   backtrace from your debugger if you break on the gdk_x_error() function.)

That has something to do with x shared memory, I don't know that that's a workrave problem. Check xdpyinfo for mit-shm