Strange Marks from my 18-55mm

Been out taking some pictures today at Haigh Hall near Wigan, and got home to find some strange....well I look at them and thing Grey Rainbows, but I'm sure there's a proper name. I've included a resize and a 100% crop of them on here. They only show up with this one lens and there's nothing "obvious" on the glass to do this either.


Any suggestions as to how I can get the lens right again? It's one of my most used

EDIT NO crop as uploader wouldn't take it :\

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Body: Camera:
Canon 350D, Canon Ixus 700
Lenses:
Canon 18-55mm f/3.5-5.6 kit lens
Canon 75-300mm f/4-5.6
Sigma 28-70mm f/2.8
Canon 50mm f/1.8
Sigma 18-50mm f/3.5-5.6
Sigma 105mm f/2.8 Macro
Canon 28-125mm f/3.5-5.6 IS
Canon 10-20mm <----best lens ever
Kit: Canon Speedlite 550 EX, Acer Travelmate C112 - Tablet PC, Apple G4 iBook - 14" with 1gb Ram,
iMac G5 with 1.5gb Ram 20"
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Brian N
7D, Rebel XT, G16, EF-S 10-22, EF-S 15-85 USM IS, Sigma 30 f/1.4, EF-S 60 macro, 85 f/1.8, EF 70-200 f/4L IS , Canon 1.4 TC, 430 EX, 270 EX
Bogen/Manfrotto 3001BPro/484RC2
Some pix at www.flickr.com/photos/​briann/

Professional wedding photographer, solution architect and general technical guy with multiple Amazon Web Services certifications.
Read all my FAQs (wedding, printing, lighting, books, etc)

5DII - 350D ; Bronica S2A, Leica IIIc&M2, Rolleiflex T etc!
Canon: 50 f1.4, 85 f1.8, 135 f2 L, 200 f2.8 L MkI, 70-300 DO
Sigma: 30 f1.4 EX, 18-200, 18-50 f2.8 EX, 28-135 Macro
Other: About 60+ Zeiss, Pentax Takumar, Meyer, Pentacon etc! http://forum.manualfoc​us.org

Body: Camera:
Canon 350D, Canon Ixus 700
Lenses:
Canon 18-55mm f/3.5-5.6 kit lens
Canon 75-300mm f/4-5.6
Sigma 28-70mm f/2.8
Canon 50mm f/1.8
Sigma 18-50mm f/3.5-5.6
Sigma 105mm f/2.8 Macro
Canon 28-125mm f/3.5-5.6 IS
Canon 10-20mm <----best lens ever
Kit: Canon Speedlite 550 EX, Acer Travelmate C112 - Tablet PC, Apple G4 iBook - 14" with 1gb Ram,
iMac G5 with 1.5gb Ram 20"
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Body: Camera:
Canon 350D, Canon Ixus 700
Lenses:
Canon 18-55mm f/3.5-5.6 kit lens
Canon 75-300mm f/4-5.6
Sigma 28-70mm f/2.8
Canon 50mm f/1.8
Sigma 18-50mm f/3.5-5.6
Sigma 105mm f/2.8 Macro
Canon 28-125mm f/3.5-5.6 IS
Canon 10-20mm <----best lens ever
Kit: Canon Speedlite 550 EX, Acer Travelmate C112 - Tablet PC, Apple G4 iBook - 14" with 1gb Ram,
iMac G5 with 1.5gb Ram 20"
[/COLOR][/COLOR]