This excerpt taken from the ELN 6-K filed Mar 30, 2007.
f Fair value gain on conversion option
From the date of adoption of IAS 32 and IAS 39 on 1 January 2005 to 28 October 2005, when the cash settlement provision that existed on issue of the 6.5% Convertible Notes was revoked, the conversion option component of the 6.5% Convertible Notes was deemed a liability, and was marked-to-market through the income statement, consistent with the accounting for other derivative assets and liabilities. The cash settlement feature was a right that was held by the parent company, as guarantor of the 6.5% Convertible Notes, and as a result, the fair value of the conversion option is accounted for in the parent company financial statements. Due to the decline in our share price from $27.25 at 1 January 2005 to $7.97 at 28 October 2005, a fair value gain of $1,136.1 million was recorded in the year ended 31 December 2005 on the conversion option component of our 6.5% Convertible Notes. From 28 October 2005, when the cash settlement option was revoked, the conversion option was recognised as the equity component of a compound financial instrument as part of shareholders equity and was not subsequently remeasured. The value of the option was fixed at $91.8 million as at 28 October 2005. For additional information, please refer to Note 22 to the Consolidated Financial Statements.