* Yen near 1-month high vs dollar
* Risk that BOJ disappoints expectations for super-aggressive easing
* ECB & BOE policy meetings also eyed
By Ian Chua and Hideyuki Sano
SYDNEY/TOKYO, April 4 (Reuters) - The yen held near one-month highs against the dollar on Thursday, with investors adopting a cautious stance as they waited to see just how aggressive the Bank of Japan will be in tackling deflation.
Having talked up expectations for bold measures, including an immediate start to its open-ended bond buying programme, the BOJ will be hard pressed to surprise markets.
Given the BOJ's track record for under delivering, the market has already trimmed back short yen positions just in case. That is one reason the yen has rallied a little in the past three weeks, coming off multi-year troughs against the dollar and euro.
The greenback fell 0.2 percent so far on Thursday to trade at 92.93 yen, near one-month low of 92.57 hit on Tuesday.
It has lost nearly 4 percent from a 3-1/2 year peak of 96.71 set a few weeks ago.
The dollar/yen looks increasingly vulnerable at least on charts, having pierced below its 55-day moving average for the first time since the yen had started declining in November.
On daily Ichimoku charts, the dollar held above an important support of cloud top, which stood at 92.20 on Thursday and will rise to 92.67 on Friday, though a break there could send a strong bearish signal.
Another support is seen around 92.55, the 23.6 percent retracement of its Nov-March rally.
Should the BOJ disappoint at this meeting, however, Nomura analysts caution that Governor Haruhiko Kuroda is very likely to try to keep expectations high for the next meeting in three weeks.
The outcome of the meeting will be announced between 0330-0530 GMT, followed by Kuroda's media briefing at around 0630 GMT.
"Thus, the press conference is likely to be a good timing of dip buying, if the market is disappointed by the announcement," Nomura analysts wrote in a client note.
The dollar came under pressure overnight also after disappointing private sector jobs data, which prompted traders to ratchet down their expectations on Friday's payrolls data.
In addition, U.S. service sector growth falls to the slowest in seven months, denting recent optimism on the U.S. economy.
Also in focus later in the day are policy meetings of the European Central Bank and Bank of England.
Both central banks are not expected to deliver any new stimulus for now, although the ECB is likely to try and calm markets by pledging to keep the banking system lubricated after Cyprus's brush with financial meltdown.
Still the risk of any surprises, such as an interest rate cut from the ECB or a restart of the BOE's bond-buying programme, is keeping investors wary of the euro and sterling.
The euro was at $1.2845, flat on the day but not far from a four-month trough of $1.2750 plumbed on March 27. Sterling was little changed at $1.5130, having dipped to a two-week low of $1.5075 on Wednesday.
The Australian dollar gained 0.2 percent to $1.0472 on surprise strength Australian retail sales. It stood near its 10-week high of $1.0498 hit on Wednesday but option-related offers at $1.05 were blocking the currency's further advance.