This are the formats you should use for command line parameters.
Do NOT modify a single character because it will not work, note that it is not case sensitive.


*.txt				Adobe Encore DVD
*.ass				Advanced SubStation Alpha
*.aqt				AQTitle
*.txt				Captions 32
*.dat				Captions DAT
*.dat				Captions DAT Text
*.txt				Captions Inc.
*.asc				Cheetah
*.txt				CPC-600
*.dks				DKS Subtitle Format
*.txt				DVD Junior
*.txt				DVD Subtitle System
*.sub				DVDSubtitle
*.txt				FAB Subtitler
*.txt				I-Author Script
*.txt				Inscriber CG
*.js;*.jss		JACOSub 2.7+
*.lrc				Karaoke Lyrics LRC
*.vkt				Karaoke Lyrics VKT
*.txt				MAC DVD Studio Pro
*.scr				MacSUB
*.sub;*.txt		MicroDVD
*.mpl				MPlayer
*.mpl				MPlayer2
*.sub				MPSub
*.ovr				OVR Script
*.pan				Panimator
*.sub				Philips SVCD Designer 1.5-2.0
*.pjs				Phoenix Japanimation Society
*.txt				Pinnacle Impression
*.psb;*.txt		PowerDivX
*.txt				PowerPixel
*.txt				QuickTime Text
*.rt				RealTime
*.smi;*.sami	SAMI Captioning
*.s2k				Sasami Script
*.sbt				SBT
*.sub				Sofni
*.rtf				Softitler RTF
*.sub				SonicDVD Creator
*.sst				Sonic Scenarist
*.son				Spruce DVDMaestro
*.stl				Spruce Subtitle File
*.sst				Stream SubText Player
*.ssts			Stream SubText Script
*.txt				SubCreator 1.x
*.srt				SubRip
*.sub				SubSonic
*.ssa				SubStation Alpha
*.sub				SubViewer 1.0
*.sub				SubViewer 2.0
*.txt;*.sub		TMPlayer
*.tts				Turbo Titler
*.txt				Ulead DVD Workshop 2.0
*.vsf				ViPlay Subtitle File
*.zeg				ZeroG
