Fetch Preview-Image failed due to COMMA instead of a DOT used in a command-option

Hey Guys,

well, I've been bussy with this for a while.

The following command is issued on machine 1:

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machine 1
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mkdir -m 0775 /movies/dvdrip-data/test/tmp/dvdrip1859.snap;  cd 
/movies/dvdrip-data/test/tmp/dvdrip1859.snap;  execflow tccat -i 
\/movies\/dvdrip\-data\/test\/vob\/006\/  -t vob -S 4689 -d 0 | tcdemux 
-s 0x80 -x mpeg2 -S 0 -M 0 -d 0 -P /dev/null | tcextract -t vob -a 0 -x 
mpeg2 -d 0 | ffmpeg -r 25.000 -i - -an -r 1 -ss '0,280' -vframes 1 
snapshot%03d.png  && execflow convert -size 720x576 
/movies/dvdrip-data/test/tmp/dvdrip1859.snap/snapshot*.png 
/movies/dvdrip-data/test/tmp/test-006-preview-orig.jpg && execflow 
convert -size 720x576 
/movies/dvdrip-data/test/tmp/dvdrip1859.snap/snapshot*.png 
gray:/movies/dvdrip-data/test/tmp/test-006-preview-orig.raw && rm -r 
/movies/dvdrip-data/test/tmp/dvdrip1859.snap && echo EXECFLOW_OK


The following command is issued on machine 2:

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machine 2
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mkdir -m 0775 /home/nico/dvdrip-data/test/tmp/dvdrip32740.snap; cd 
/home/nico/dvdrip-data/test/tmp/dvdrip32740.snap; execflow tccat -i 
\/home\/nico\/dvdrip\-data\/test\/vob\/006\/  -t vob -S 4689 -d 0 | 
tcdemux -s 0x80 -x mpeg2 -S 0 -M 0 -d 0 -P /dev/null | tcextract -t vob 
-a 0 -x mpeg2 -d 0 | ffmpeg -r 25.000 -i - -an -r 1 -ss '0.280' -vframes 
1 snapshot%03d.png  && execflow convert -size 720x576 
/home/nico/dvdrip-data/test/tmp/dvdrip32740.snap/snapshot*.png 
/home/nico/dvdrip-data/test/tmp/test-006-preview-orig.jpg && execflow 
convert -size 720x576 
/home/nico/dvdrip-data/test/tmp/dvdrip32740.snap/snapshot*.png 
gray:/home/nico/dvdrip-data/test/tmp/test-006-preview-orig.raw && rm -r 
/home/nico/dvdrip-data/test/tmp/dvdrip32740.snap && echo EXECFLOW_OK


The command finishes succesfully on machine 2, unfortunately not on 
machine 1.  I found kind of a small difference ....

machine 1:  -ss '0,280'
machine 2:  -ss '0.280'

On machine 1 dvdrip uses an COMMA. On machine 2 dvdrip insert a DOT.
If I execute the command on machine 1 manually with a DOT instead of a 
COMMA, the command finishes nicely.

Well, .... actually I don't know what to do .... Is this a perl issue ?

Greetings,

Nico