DCMTK

Currently, multiple value matching is implemented to match N query values with M stored values and, if any of them match, return a match as the result. It is debatable whether the standard can be read like this or whether the query attribute must alwasy contain a single value only. If multiple value querys are forbidden, the implementation would not really be wrong since it would be operating on invalid data anyway, put perhaps emitting a warning in that case would be appropriate.