Sweden is not the only country that considers sex with someone sleeping or otherwise unconscious as rape; a quick look at UK law for instance seems to bring this up in section 75 (http://www.legislation.gov.uk/ukpga/2003/42). Even in Mr. Assange's native Australia, failure to withdraw from sexual intercourse after consent is withdrawn appears in itself to be considered "rape" in all districts but Queensland. (https://www.alrc.gov.au/publications/25.%20Sexual%20Offences...)

There are varying degrees of rape in Sweden, as I understand it Mr. Assange is being accused of the most minor degree of rape due to the circumstances. Still, it seems like what he is accused of is typically labeled "rape" in many places.