need some help with sed

[crzyOrc]

Hi,
i have a log file look like this:
/WebBug.aspx AdvertiserId=991&ConversionId=1333&DmgContext=7d84 d9aa4db949f9a0f325ca5c9b65fa - HTTP/1.1 Mozilla/5.0+(Windows;+U;+Windows+NT+6.1;+en-US;+rv:1.9.2)+Gecko/20100115+Firefox/3.6

/WebBug.aspx AdvertiserId=991&ConversionId=1333&DmgContext=87a4 72fa1e004d70ae347a262d3bba7d - HTTP/1.1 Mozilla/5.0+(Windows;+U;+Windows+NT+6.1;+en-US;+rv:1.9.2)+Gecko/20100115+Firefox/3.6

/WebBug.aspx AdvertiserId=991&ConversionId=1333&DmgContext=c5dc 5d30845c49bda50b102cb2aaf37d - HTTP/1.1 Mozilla/5.0+(Windows;+U;+Windows+NT+6.1;+en-US;+rv:1.9.2)+Gecko/20100115+Firefox/3.6

i want to display just the part of the DmgContext=c5dc5d30845c49bda50b102cb2aaf37d in every line

i tried to do so with SED but with no success.

PLEASE HELP ME