diff --git a/src/main/java/org/jenkinsci/plugins/jobgenerator/GeneratorRun.java b/src/main/java/org/jenkinsci/plugins/jobgenerator/GeneratorRun.java
index aa5590b..bf74706 100755
--- a/src/main/java/org/jenkinsci/plugins/jobgenerator/GeneratorRun.java
+++ b/src/main/java/org/jenkinsci/plugins/jobgenerator/GeneratorRun.java
@@ -35,6 +35,7 @@ import hudson.model.AbstractProject;
 import hudson.model.Cause;
 import hudson.model.ParametersAction;
 import hudson.model.Run;
+import hudson.model.StringParameterValue;
 import hudson.plugins.parameterizedtrigger.AbstractBuildParameters;
 import hudson.plugins.parameterizedtrigger.BlockableBuildTriggerConfig;
 import hudson.plugins.parameterizedtrigger.BuildTrigger;
@@ -120,8 +121,12 @@ public class GeneratorRun extends Build<JobGenerator, GeneratorRun> {
             for (ParametersAction p : params) {
                 List<ParameterValue> values = p.getParameters();
                 for (ParameterValue v : values) {
+                    if(!(v instanceof GeneratorKeyValueParameterValue) && (v instanceof StringParameterValue)){
+                        v = new GeneratorKeyValueParameterValue((StringParameterValue)v);
+                    } 
                     s = GeneratorRun.expand(s, v.getName(),
                                   ((GeneratorKeyValueParameterValue) v).value);
+                    
                 }
             }
             // replace nested variables
diff --git a/src/main/java/org/jenkinsci/plugins/jobgenerator/parameters/GeneratorKeyValueParameterValue.java b/src/main/java/org/jenkinsci/plugins/jobgenerator/parameters/GeneratorKeyValueParameterValue.java
index f17c35f..420d854 100644
--- a/src/main/java/org/jenkinsci/plugins/jobgenerator/parameters/GeneratorKeyValueParameterValue.java
+++ b/src/main/java/org/jenkinsci/plugins/jobgenerator/parameters/GeneratorKeyValueParameterValue.java
@@ -51,6 +51,10 @@ public class GeneratorKeyValueParameterValue extends StringParameterValue {
         super(name, description);
         this.value = value;
     }
+    
+    public GeneratorKeyValueParameterValue(StringParameterValue spv){
+        this(spv.getName(), spv.value, spv.getDescription());
+    }
 
     /**
      * Exposes the name/value as an environment variable.