Check if that $_SERVER param is set before accessing.
Check if that $_SERVER param is set before accessing.

zcopley/zcopleys-statusnet-clone,xebia/statusnet-oauth2,minmb/statusnet,sikevux/bsk-social,znarf/statusnet-ladistribution,furtherfield/gnu-social,zh/statusnet,d3vgru/StatusNet,bankonme/gnu-social,shashi/StatusNet,csarven/statusnet,d3vgru/StatusNet,minmb/statusnet,gnusocial/mainline,bankonme/gnu-social,sikevux/bsk-social,bankonme/gnu-social,chimo/social,furtherfield/gnu-social,gnusocial/mainline,zcopley/zcopleys-statusnet-clone,charnimda/lgbtpzn-social,charlycoste/StatusNet,minmb/statusnet,faulteh/gnu-social,csarven/statusnet,gnusocial/mainline,xebia/statusnet-oauth2,meitar/laconica,Piratas/tortuga,shashi/StatusNet,charlycoste/StatusNet,zcopley/StatusNet,gnusocial/mainline,faulteh/gnu-social,foocorp/gnu-social,sikevux/bsk-social,studio666/gnu-social,faulteh/gnu-social,furtherfield/gnu-social,zcopley/StatusNet,eXcomm/gnu-social,zcopley/zcopleys-statusnet-clone,d3vgru/StatusNet,charnimda/lgbtpzn-social,znarf/statusnet-ladistribution,eXcomm/gnu-social,studio666/gnu-social,eXcomm/gnu-social,studio666/gnu-social,faulteh/gnu-social,chimo/social,Br3nda/laconica,shashi/StatusNet,UngPirat/freesocial,brion/StatusNet,zh/statusnet,charlycoste/StatusNet,UngPirat/freesocial,zcopley/StatusNet,brion/StatusNet,Br3nda/laconica,meitar/laconica,chimo/social,foocorp/gnu-social,Br3nda/laconica,csarven/statusnet,Piratas/tortuga,zh/statusnet,Piratas/tortuga,sikevux/bsk-social,csarven/statusnet,UngPirat/freesocial,foocorp/gnu-social,brion/StatusNet,znarf/statusnet-ladistribution,eXcomm/gnu-social,xebia/statusnet-oauth2,furtherfield/gnu-social,bankonme/gnu-social,charnimda/lgbtpzn-social,Piratas/tortuga,studio666/gnu-social,meitar/laconica