minipage and vertical spacing, parskip

I noticed that my \parskip was ignored by the "minipage" environment. After some investigations I found that many vertical spacing commands have a special behaviour inside a minipage, and that the command "if@minipage" is used quite often.

Here are my questions in comp.text.tex:

What is the reason for such behaviour?

Where could I read about it?

By the way, here is how I restore the value of a \parskip inside a "minipage":

\\let\\V@oldminipagerestore\\@minipagerestore
\\def\\@minipagerestore{\\V@oldminipagerestore
  \\setlength{\\parskip}{X plusY minusZ}}

I'm not sure it is the right way, but I don't see an alternative.

Categories: TeX