The ISE Euro Index (.EUI) is seeing bullish order flow. The EUI is a cash index that tracks the performance of the euro against the dollar. Like other ISE currency indices, it is dollar-based and therefore will move higher with the dollar. Today, for example, the EUI was able to shake off early weakness and trade up 33 cents to 65.23 after the euro fell to 1.533 against the buck (1/1.533 = .6523). The euro is seeing some volatility Thursday after the European Central Bank [ECB] voted to leave interest rates unchanged and ECB Prez Trichet noted downside risks to growth.

That, in turn, seems to be viewed as a bullish development for the dollar in the eyes of some traders. Volume in the EUI is running 40 times the usual, with more 5,000 calls and 720 puts traded on the session. 3,000 of the December 66s and 2,000 of the March 66.5 calls traded offerside.

Meanwhile, some players bought opened bear put spreads on the Currency Shares Euro trust (FXE), which is an exchange traded fund [ETF] that tracks the euro (moves inversely to the dollar). For example, at 10:45 Eastern time, an order of 1000 FXE September 152 puts traded offerside for $1.30 a contract on the PHLX. At the same time, 1,000 of the September 149s traded bidside for 40 cents a contract. The trade was repeated several times and the volume in those two contracts is more than 4,000 contracts (2,000 each), and well above exsiting open interest. Therefore, in this case, traders seem to be opening bearish spreads on the FXE, which would also represent bullish bets on the buck.