Spaces and %HH in part names

[MURATA Makoto (FAMILY Given)]

> I did a bit of investigation after the call, and it would appear that MS Office will not open a file which contains a part name with spaces in it, and will certainly not create one. LibreOffice opened my sample file (perhaps this is a due to ODF permitting spaces?) but resaved it without the spaces. Given that they're also precluded by the BNF, I think this means we can safely say that nobody's using them. A sample file is attached in case anyone wants to test it elsewhere.
> 
> Murata-san - do you happen to have the EPUB wording for recommending ASCII? I think I'll make the initial steps of writing up the necessary changes to Part 2.

The latest EPUB spec about this topic is:

http://idpf.org/epub/30/spec/epub30-ocf.html#sec-container-filenames

My attempt to harmonize ZIP item names in EPUB and those in OPC is
available at:

http://code.google.com/p/epub-revision/issues/detail?id=125&can=1&q=OCF

However, since existing EPUB2 publications are likely to use the space
character as a part of ZIP item names.  Thus, my proposal to disallow 

0020 SPACE
0023 NUMBER SIGN
0025 PERCENT SIGN
003B SEMICOLON
005B LEFT SQUARE BRACKET
005D RIGHT SQUARE BRACKET
005E CIRCUMFLEX ACCENT
0060 GRAVE ACCENT
007B LEFT CURLY BRACKET
007C VERTICAL LINE
007D RIGHT CURLY BRACKET
007E TILDE

(which are not allowed by  ipchar of RFC 3987) was not 
accepted.  

Cheers,
Makoto