Error message in log every 1 to 10 seconds

[13-02-08 15:53:05.1804] Slim::Web::Cometd::handler (421) errorNeedsClient: 00:04:20:1b:6e:b8, status, -, 10, menu:menu, useContextMenu:1, subscribe:600
[13-02-08 15:53:08.4816] Slim::Web::Cometd::handler (421) errorNeedsClient: 00:04:20:1b:6e:b8, status, -, 10, menu:menu, useContextMenu:1, subscribe:600
[13-02-08 15:53:11.2228] Slim::Web::Cometd::handler (421) errorNeedsClient: 00:04:20:1b:6e:b8, status, -, 10, menu:menu, useContextMenu:1, subscribe:600
[13-02-08 15:53:12.7619] Slim::Web::Cometd::handler (421) errorNeedsClient: 00:04:20:1b:6e:b8, status, -, 10, menu:menu, useContextMenu:1, subscribe:600
[13-02-08 15:53:17.2629] Slim::Web::Cometd::handler (421) errorNeedsClient: 00:04:20:1b:6e:b8, status, -, 10, menu:menu, useContextMenu:1, subscribe:600
[13-02-08 15:53:19.8242] Slim::Web::Cometd::handler (421) errorNeedsClient: 00:04:20:1b:6e:b8, status, -, 10, menu:menu, useContextMenu:1, subscribe:600
[13-02-08 15:53:21.8728] Slim::Web::Cometd::handler (421) errorNeedsClient: 00:04:20:1b:6e:b8, status, -, 10, menu:menu, useContextMenu:1, subscribe:600
[13-02-08 15:53:24.2185] Slim::Web::Cometd::handler (421) errorNeedsClient: 00:04:20:1b:6e:b8, status, -, 10, menu:menu, useContextMenu:1, subscribe:600

These messages are filling my server.log. Anyone who knows what these messages mean?

Server:
Logitech Media Server Versie: 7.8.0 - 1353679004 @ Sat Nov 24 03:08:42 PST 2012
Hostnaam: Server
IP: 192.168.2.8
HTTP-poort: 9000
Besturingssysteem: - NL - cp1252
Platform: 8664
Perl-versie: 5.14.1 - MSWin32-x86-multi-thread
Databaseversie: DBD::SQLite 1.34_01 (sqlite 3.7.7.1)
Totaalaantal herkende muzieksystemen: 6

Regards,
Stephan van der Plas