diff --git a/GSM411.st b/GSM411.st
index 2ecc6f1..f1f7f14 100644
--- a/GSM411.st
+++ b/GSM411.st
@@ -59,23 +59,27 @@ GSM48FixedSizeIE subclass: GSM411RpMessageReference [
 GSM48DataHolder subclass: GSM411RpOriginatorAddress [
     <category: 'OsmoGSM-SMS-Types'>
     <comment: '8.2.5.1'>
+    <gsmMinValueSize: 0 max: 11>
 ]
 
 GSM48DataHolder subclass: GSM411RpDestinationAddress [
     <category: 'OsmoGSM-SMS-Types'>
     <comment: '8.2.5.2'>
+    <gsmMinValueSize: 0 max: 11>
 ]
 
 GSM48DataHolder subclass: GSM411RpUserData [
     <category: 'OsmoGSM-SMS-Types'>
     <comment: '8.2.5.3'>
     <gsmElementId: 2r1000001>
+    <gsmMinValueSize: 0 max: 233>
 ]
 
 GSM48DataHolder subclass: GSM411RpCause [
     <category: 'OsmoGSM-SMS-Types'>
     <comment: '8.2.5.4'>
     <gsmElementId: 2r1000010>
+    <gsmMinValueSize: 1 max: 2>
 
     GSM411RpCause class [
         "MO Causes"
diff --git a/GSM48.st b/GSM48.st
index 525de08..feafb45 100644
--- a/GSM48.st
+++ b/GSM48.st
@@ -95,11 +95,6 @@ GSM48IE subclass: GSM48FixedSizeIE [
             gsmValueLength := aLength
         ]
 
-        gsmValueLength [
-            <category: 'gsm-pragma'>
-            ^gsmValueLength
-        ]
-
         classPragmas [
             <category: 'gsm-pragma'>
             ^super classPragmas, #(#gsmValueLength)
@@ -118,7 +113,10 @@ GSM48IE subclass: GSM48FixedSizeIE [
 
         gsmValueLength [
             <category: 'parsing'>
-            ^ gsmValueLength ifNil: [self superclass gsmValueLength]
+            ^ gsmValueLength ifNil: [
+                self = GSM48FixedSizeIE
+                    ifTrue: [nil]
+                    ifFalse: [self superclass gsmValueLength]]
         ]
 
         asTLVDescription [
@@ -155,12 +153,16 @@ GSM48IE subclass: GSM48VariableSizedIE [
 
         gsmValueSizeMin [
             <category: 'gsm-pragma'>
-            ^gsmValueRange first
+            ^(self = GSM48VariableSizedIE or: [self = GSM48DataHolder])
+                ifTrue: [nil]
+                ifFalse: [gsmValueRange first]
         ]
 
         gsmValueSizeMax [
             <category: 'gsm-pragma'>
-            ^gsmValueRange last
+            ^(self = GSM48VariableSizedIE or: [self = GSM48DataHolder])
+                ifTrue: [nil]
+                ifFalse: [gsmValueRange last]
         ]
 
         gsmValueSizeMin: aMin [
@@ -834,6 +836,7 @@ GSM48VariableSizedIE subclass: GSM48MIdentity [
 
     <gsmElementId: 23>
     <gsmName: 'mi'>
+    <gsmMinValueSize: 1 max: 8>
 
     GSM48MIdentity class >> createDefault [
         <category: 'creation'>
@@ -1988,6 +1991,7 @@ GSM48NetworkName subclass: GSM48ShortName [
     <comment: '10.5.3.5a'>
     <gsmElementId: 16r45>
     <gsmName: 'shortNetworkName'>
+    <gsmMinValueSize: 1 max: 128>
 ]
 
 GSM48SimpleData subclass: GSM48TimeZone [