using MD5 password encryption instead of Crypt

I have question accrding to changing crypt to md5 as desribed in
http://www.howtoforge.com/ispconfig-2.x-first-steps-p2 section 2.2.4

When i do this change on living ISPC with 100+ websites, will this affect existing passwords? Can i do this on production server?

Thanks in advance for advise

 

Yes, that's no problem. Linux can handle both password types at the same time.

 

THANKS!

then i'm wondering why is it not set by default...