Hape was cited by French match commissioner Yves Thieffine for the tackle on Edinburgh back-row forward David Denton in the Heineken Cup last Saturday.
The Exiles star cannot play again until December 15, meaning he will miss Heineken Cup games against Cardiff Blues and Racing Metro, plus Aviva Premiership appointments with Wasps and Saracens.
Hape, who signed for Irish from their Premiership rivals Bath earlier this year, pleaded guilty to the offence at a hearing on Thursday, when Exiles rugby director Toby Booth and team manager Kieran McCarthy made representations on his behalf.
Hape was reported for being in contravention of Law 10.4 (e) - "dangerous tackling of an opponent, including a tackle or an attempted tackle above the line of the shoulders even if the tackle starts below the line of the shoulders."
Judicial officer Robert Williams upheld the citing complaint and decided the offence was mid-range in terms of its seriousness level with entry point of six weeks.
"When considering aggravating factors, the judicial officer added one week," said European Rugby Cup, in a statement.
"Having then taken into account mitigating factors, including the player's guilty plea, clean record and clear remorse, the judicial officer reduced the period of suspension by the maximum amount of 50 per cent.
"As suspensions are rounded up to whole weeks, the player was suspended for a period of four weeks."
Hape has the right of appeal, but his absence for two European games is a blow to Irish, who are already on the back foot in terms of qualifying from their pool following a narrow home defeat against Edinburgh.
Meanwhile, Perpignan's French centre David Marty has been banned for four weeks after admitting to a dangerous tackle on Exeter wing Gonzalo Camacho during the second half of their Amlin Challenge Cup clash last Friday.
Marty pleaded guilty of a lift tackle in violation of law 10.4 (j), which carries a ban of up to six weeks.
Marty will be available again from Thursday, December 15.
Gilbert has released a new line of rugby cleats. The Gilbert Virtuo 8S is part of the exciting new product. Check it out.
The entire All Blacks apparel line has been updated for 2013/14. Check out the New Zealand All Blacks polo.
The Nike Tiempo is a solid rugby cleat and one of few styles still made from full-grain natural leather.
The Gilbert Blitz 8S rugby cleat is a great cleat at a great price of $69.99. Get a new pair of cleats today.
A cool looking all black rugby cleat with the high performance adidas is known for. Get in the Gear!
Wear the crest of the British and Irish Lions on your t-shirt. A great look for the summer.
The All Blacks Performance t-shirt is black with hints of blue from the training jersey. Very Cool.
The New Zealand All Blacks training jersey for 2013/14. Get in the Gear!
The USA Rugby Pro Alternate rugby jersey is perfect for any fan of the Eagles. Get yours to wear during the summer Test matches.
The NEW All Blacks 2013/14 jersey has arrived at World Rugby Shop. Dare to wear the colors of the All Blacks.