name and sid attribute in <rigid_body> are of type NCName, which means they are not allowed to contain spaces or colons, even when you put quotes around it. (unless I misunderstood)
Someone brought up the discussion that 3DS Max names the bones with spaces. The naming becomes a issue when you convert the skeleton into a ragdoll and create rigid bodies for each bone.
Do we need to convert them in underscores? How do people deal with this naming issue?By default 3D Studio max creates a ‘biped skeleton’ which has spaces in it.
From COLLADA 1.41 Specification pdf from khronos.org/collada website:
Quote from XML.COM
NCName The XSLT specification describes many components of XSLT syntax as "NCNames," a term that comes from the W3C namespace specification. To simplify a little, an NCName is any name that begins with a letter or underscore and has no space or colon in it ("NC" = "No Colon" ). It can't have a colon because it may have a namespace prefix added to its beginning, and namespace prefixes themselves are also defined as NCNames. Because the prefix and the part after it are connected by a colon, a colon within these names would confuse a processor trying to figure out where the prefix ended and the other part began, so they both must be "No Colon" names. See also "QName."