Patent back door for Sun? (ODF all versions)

["Alex Brown" <alexb@griffinbrown.co.uk>]

As I understand it, the IPR regime governing ODF is in part comprised of
Sun's non-assertion statement (http://is.gd/liv1). According to this,

"Sun irrevocably covenants that [...] it will not seek to enforce any of
its enforceable U.S. or foreign patents against any implementation of
the Open Document Format for Office Applications (OpenDocument) v1.0
Specification, or of any subsequent version thereof ("OpenDocument
Implementation") in which development Sun participates to the point of
incurring an obligation, as defined by the rules of OASIS [...]"

We learn about such an "obligation" from the OASIS rules
(http://is.gd/livR), and that, for a party withdrawing from a TC:

"A TC Party that has incurred a Participation Obligation prior to
withdrawal continues to be subject to its Participation Obligation but
only with respect to OASIS Draft Deliverable(s) approved more than seven
(7) calendar days prior to its withdrawal." 

IANAL, but is a correct reading of this that if Sun withdraws from the
ODF TC, then all outputs of the TC (and implementation of outputs)
dating from 7 days prior to that date, and extending into the future,
are fully subject to any patent claims Sun might then make? (I notice
the verb form here is "participates", not "has participated"). Perhaps a
more legally-minded reader could clarify ...

If this is the case, is this acceptable to OASIS? I doubt it would be
acceptable to JTC 1 (newly sensitized to IPR issues by events
elsewhere), or to the "FOSS community", who enjoy a distinctly
problematic relationship with Sun.

What is needed here is a clearly-stated, perpetual waiver of patent
rights from all parties who potentially hold them, that applies to all
ODF drafts, specifications and standards published by OASIS embodying
those technologies; not a hard-to-parse, qualified and conditional
waiver. DIS 29500 has taught us that such clarity is necessary.

Enlightenment / reassurance please!

- Alex.