Hibernate Query Question - Get most recent unique rows

Given the two classes at the bottom of this email, I'm having trouble
coming up with a Hibernate query statement that returns a list
representing all rows in the quality_control_reset table where there is
only one row for the most recent quality_control_range. Help?

Example:

In table quality_control_reset, there are the following rows:

id | timestamp | qualitycontrolrange
---------------------------------------------
1 | 02/23/2006 | 20
2 | 02/23/2006 | 6
3 | 02/28/2006 | 18
4 | 03/01/2006 | 18
5 | 03/23/2006 | 12
6 | 03/23/2006 | 20

I want the results of the following from the query:

id | timestamp | qualitycontrolrange
---------------------------------------------
2 | 02/23/2006 | 6
4 | 03/01/2006 | 18
5 | 03/23/2006 | 12
6 | 03/23/2006 | 20

QualityControlReset.java:

package test;

import java.util.Date;

/**
* @hibernate.class table="quality_control_reset"
*/
public class QualityControlReset {
private Date date;
private QualityControlRange qualityControlRange;

public QualityControlReset() {
// noop
}

/**
* @hibernate.id generator-class="native" column="id"
*/
public Long getId() {
return id;
}

public void setId(Long long1) {
id = long1;
}

/**
* @hibernate.property not-null="true"
*/
public Date getDate() {
return date;
}

public void setDate(Date date) {
this.date = date;
}

/**
* @hibernate.many-to-one class="test.QualityControlRange"
cascade="none" not-null="true"
*/
public QualityControlRange getQualityControlRange() {
return qualityControlRange;
}

public void setQualityControlRange(QualityControlRange
qualityControlRange) {
this.qualityControlRange = qualityControlRange;
}
}

QualityControlRange.java:

package test;

/**
* @hibernate.class table="quality_control_range"
*/
public class QualityControlRange {
private String code;

public QualityControlRange() {
}

/**
* @hibernate.id generator-class="native" column="id"
*/
public Long getId() {
return id;
}

public void setId(Long long1) {
id = long1;
}

/**
* @hibernate.property
*/
public String getCode() {
return code;
}

public void setCode(String code) {
this.code = code;
}
}