Upgrading Plugin from CRM 4 to CRM 2011

I need to upgrade this plugin from CRM 4 to CRM 2011:

using System;
using System.Collections.Generic;
using System.Text;
using FilterServiceQueues.CrmSdk;
using Microsoft.Crm.Sdk;
using Microsoft.Crm.SdkTypeProxy;

namespace FilterServiceQueues
{
    public class RemoveQueues : IPlugin
    {
        #region IPlugin Members

        public void Execute(IPluginExecutionContext context)
        {
            //System.Diagnostics.Debugger.Launch();

            foreach (PropertyBagEntry item in context.InputParameters.Properties)
            {
                if (item.Name == "Query")
                {
                    Microsoft.Crm.Sdk.Query.QueryExpression queryExpression = item.Value as Microsoft.Crm.Sdk.Query.QueryExpression;

                    foreach (Microsoft.Crm.Sdk.Query.ConditionExpression conditionExpression in queryExpression.Criteria.Conditions)
                    {
                        if ((conditionExpression.AttributeName == "queuetypecode") &&
                            (conditionExpression.Operator == Microsoft.Crm.Sdk.Query.ConditionOperator.Equal) &&
                            (conditionExpression.Values[0].ToString() == "1"))
                        {
                            queryExpression.Criteria.Conditions.Remove(conditionExpression);
                            queryExpression.Criteria.Filters.Add(newFilterExpression(context));
                            break;
                        }

                    }
                }
            }
        }
        #endregion

        public Microsoft.Crm.Sdk.Query.FilterExpression newFilterExpression(Microsoft.Crm.Sdk.IPluginExecutionContext context)
        {
            Microsoft.Crm.Sdk.Query.ConditionExpression condition1 = new Microsoft.Crm.Sdk.Query.ConditionExpression();
            condition1.AttributeName = "queuetypecode";
            condition1.Operator = Microsoft.Crm.Sdk.Query.ConditionOperator.Equal;
            condition1.Values = new object[] { "1" };

            Microsoft.Crm.Sdk.Query.ConditionExpression condition2 = new Microsoft.Crm.Sdk.Query.ConditionExpression();
            condition2.AttributeName = "businessunitid";
            condition2.Operator = Microsoft.Crm.Sdk.Query.ConditionOperator.Equal;
            condition2.Values = new object[] { context.BusinessUnitId };

            Microsoft.Crm.Sdk.Query.FilterExpression filterExpression = new Microsoft.Crm.Sdk.Query.FilterExpression();
            filterExpression.FilterOperator = Microsoft.Crm.Sdk.Query.LogicalOperator.And;
            filterExpression.Conditions.Add(condition1);
            filterExpression.Conditions.Add(condition2);

            return filterExpression;

        }

    }
}

Is there any converter or methodology? Anyone could help me on this conversion?

Any helps would be appreciated.