Since jack audio support has been working in VLC for quite some time, a jack USE flag should be added to VLC.
Created attachment 103850 [details, diff] Patch to vlc-0.8.6.ebuild to add a jack USE flag The patch is tested and working on amd64 system.
Created attachment 103851 [details, diff] Patch to vlc-0.8.5-r5.ebuild to add a jack USE flag The patch is tested and working on amd64 system.
Jack support seems to be fine now, added to ~arch vlc, thanks for reporting.