ALMAS12 — Ambiguity in dynamic message data substitution

The description of class DynamicMessageData and its DataTag attribute is ambiguous as to whether one or two percent (%) markers are required. Also the protocol is ambiguous when there are 10 or more markers. Also, particularly with a single % marker there isn't a defined way to escape the markers.

Clarify Dynamic Message Substitution

Placeholder tags to be designated by a single exclosing percent characters.
Multiple - in principle unbounded - replacements supported with each tag enclosed by space (or other non-alphanumeric character). The examples given in the current specification (t1, tn) are examples and more meaningful tags can be used and are encouraged (e.g. %number%, %score% or %name%).
It is not necessary to provide a means of specifying a way to express %name% as a literal substring in a static message as this would have no meaning to a system user.
Additionally, it should be possible to specify a replacement at the start or end of the static message. Equally it should be possible to have dynamic data at the start or end of the message and it should be possible to use punctuation around it (e.g. a comma). Therefore substitution points should be defined by:
(start | non-alphanumeric)%t(numeric){end | non-alphanumeric)
It is an error to specify static and dynamic data message instances with different substitution tags for the same alert template. In particular all static message instances (for different language locales) must have the same substitution set.