No 9578, Tuesday, 07 Jul 09, Neyartha

An equatorial exercise today. 9D eludes me
Note: Solutions to the starred clues (which carry no direct definition) share the commonality of straddling the biggest circle on earth.
ACROSS
1 - Shy girl’s pig let loose on saint taking off in a Victorian manner (10) - PRIGGISHLY(-s)*
6 - Cycles made with silver and selenium from the east (4) - {AG}{ES<-} )
10 - JBA? He is a Jack of all trades (3-3,3) - ODD-JOB MAN [CD] What is JBA here ?
11 - Go slowly? That is a risky move after losing the opener (5) - (-g)AMBLE
12 - Night sky pattern (13) - CONSTELLATION [CD]
14 - Mani suspects hidden strain (5) - NISUS [T]
15 - Can ethylene catalysis remove hydrogen and nitrogen from welder’s gas? (9) - ACETYLENE(h-n)*
17 - Capital city (old) shelters bishop framed by the French military alliance (4,5) - U{LA}{N {B}ATO}R
21 - Organic compound in the clear upper air (5) - ETHER [CD]
22 - Camel in the desert (5,2,6) - BEAST OF BURDEN [CD]
24 - Court excuse (5) - ALIBI [CD]
25 - Ended Verdi composition in high gear (9) - {OVER}{DRIVE*}
26 - Proverbial necessity for you to find (4) - SEED [CD] (Correction - SEEK)
27 - Cowboy films featuring hesitation of Americans, for example (10) - WESTERN{ER}S
DOWN
1 - Poem incurs trouble in this part of the stage (10) - PROSCENIUM*
2 - *Singles in our country (9) - IND{ONES}IA
3 - Engineer got slit in a part of the throat (7) - GLOTTIS*
4 - *Trouble brought about by Vedic intoxicant in the beginning (7) - {SOMA}{LIA<-} )
5 - Take time out to sort gelatine stock (7) - LINEAGE(-t)*
7 - *Silver sent up to a German city for the auditor (5) - {GA<-}{BON}(~bonn)
8 - Appear to give 26 Ac a 1000 fold increase at the end (4) - SEEM(-d+m) Correction - (-k+m)
9 - Correspondence with one taken in by revolutionary Yankee’s trickery (6) - PARITY ? (Addendum - PAR{I}T<-{Y} - See Chaturvasi's comments below)
13 - Pistols found with the German impostors (10) - {DER}{RINGERS}
16 - Uncontrollably pined here for asthma medicine (9) - EPHEDRINE*
18 - *Sail rope ensnares Zulu chief (6) - BRA{Z}IL
19 - Got across note to replace Siemens vacuum tube (7) - (-s+te)TETRODE
20 - Mirror show (7) - REFLECT [DD]
21 - *Doctors, discouraged, quit digs (7) - ECUADOR(-digs)*
22 - Pool material made from Mediterranean trees reportedly (5) - BAIZE (~bays)
23 - Lacking in letters of bipartisan support (4) - SANS [T]