A STREET sleeper who needed money to buy heroin succeeded in holding up a bank with a wooden stick, the High Court heard yesterday. Sentencing casual worker Cheung Kwok-hung, 44, to four years' jail, Deputy Judge Daniell said the offence must have caused distress to the bank teller who received Cheung's threatening note. Cheung, who had been addicted to drugs for more than 20 years, admitted one count of robbing the Standard Chartered Bank. Prosecutor Harish Melwaney told the court that Cheung approached a counter in the bank's Waterloo Road branch shortly before 1 pm on May 14 last year and presented a deposit slip. On seeing written on it the words: ''be silent, with pistol, demand money'', and fearing there was a pistol in the bag Cheung was carrying, the teller handed over $19,000 cash after activating the surveillance camera. When Cheung was arrested on July 3 last year he admitted the offence, claiming that he had carried a wooden stick in the bag and pretended that it was a gun. Dennis Law, counsel for Cheung, accepted that his client had more than 20 previous convictions, including theft, robbery and drug offences. He said Cheung had been an addict for more than 20 years and only committed the holdup on the spur of the moment to feed his habit.