[ OT ] local packages vs official packages

[Samu <samu@linuxasylum.net>]

hi,
this is just a curiosity, i think is not so security related, aniway...
if i made a package by my self, or from deb sources, of a package
that already exist on to the debian db, and my "local" package is
called as the official one, when i run then dselect or apt, they overwrite
my local pkg for the official one.
i have to explicity "hold" the local package to not to have overwritten.
why ? they aren't checked only for the version number ? 

Could it be dangerous ? ( e.g. local package was compiled to fix the official
package that was broken and not fixed ) 

TIA

Samuele 

-- 
Samuele Tonon  <samu@linuxasylum.net>
Undergraduate Student  of  Computer Science at  University of Bologna, Italy    
System administrator at Computer Science Lab's, University of Bologna, Italy  
Founder & Member of A.A.H.T.
UIN 3155609 
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