no syntax color for big files

Hello,

I have noticed that whenever I open a large file, for instance a fortran 
file of more than 10,000 lines in xemacs it shows in plain black and 
white. Different colors I typically see for different syntax in program 
does not seem to work. For all normal (not so large) files it works 
fine. Ofcourse I have enabled syntax highlight. Any idea or similar 
experience ? I am using linux RH 9.0.

Thanks
Rishi

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