XML spec: Why is colon ':' a NameStartChar?

Why is colon ':' a NameStartChar [A]?
It produces XML parsing error.
I found nothing in the errata [B], what am I missing?


[40] STag  ::=   '<' Name (S Attribute)* S? '>'	[WFC: Unique Att Spec]

[5]  Name  ::=   NameStartChar (NameChar)*

[4]  NameStartChar ::=   ":" | [A-Z] | "_" | [a-z] | [#xC0-#xD6] | ...


[A] http://www.w3.org/TR/xml/#NT-NameStartChar
[B] http://www.w3.org/XML/xml-V10-5e-errata


Mit besten Gruessen / Best wishes,

Hermann Stamm-Wilbrandt
Level 3 support for XML Compiler team and Fixpack team lead
WebSphere DataPower SOA Appliances
https://www.ibm.com/developerworks/mydeveloperworks/blogs/HermannSW/
https://twitter.com/HermannSW/     http://www.stamm-wilbrandt.de/frameless/
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