Eph.4/Jeff Warner

A buddy and I have been working through Eph. 4:11-12 and are considering the
following questions.  Any grammatical insights would be appreciated:

Very rough translation [v.11]:  'And he gave some [to be] apostles, some
prophets, some evangelists, and some pastor-teachers ...'

                   (now here's the crux of our referent question)

[v.12 -- read as a 3-fold job description of their (apostles, prophets, etc.)
common work]: 'to make the saints complete, [to do] works of ministry, and
[to] build up the body of Christ ...'


[v.12 -- read as a single job description, with "the saints" being the agents
of the last two activities]:  that they[apostles] make the saints complete,
in order that they [saints] may do works of ministering and [the saints] may
build up the body of Christ ...'

My knee-jerk reaction is to go with the latter -- noting especially the
change in prepositions from "pros" to "eis."  But Robertson's "A Grammar of
the Greek New Testament" (p.624.6) notes that Mark 11:1 and Phil.5 as
examples of distinctive use of the two prepositions, but then goes on to say
"that distinction hardly applies in Ro. 3:25f; Eph. 4:12."  We note also the
common agent, God, with both the "pros" and the "eis" clauses in Ro. 3:25f.
Interesting that Ro. 3 and Eph. 4 have the "dwrean" and "edwken"
(respectively) in common -- is that relevant?