Version:           unspecified (using KDE 4.5.0) 
OS:                Solaris

The problem is in kdirmodel.cpp and initial m_childCount value.

It seems that the constructor of KDirModelNode should set its m_childCount to KDirModel:ChildCountUnknown (== -1) so that it could be determined to be set to an actual value during the first read of the directory.

However the statement
  int m_childCount:31;
in the KDirModelNode class definition causes m_childCount to have a value of 2147483647 on Solaris, which is then passed on as a number of items in the directory.

--- kdirmodel.cpp.orig  2010-08-14 14:08:47.600811777 +0000
+++ kdirmodel.cpp       2010-08-14 14:02:08.221257739 +0000
@@ -112,7 +112,7 @@
     }
 
 private:
-    int m_childCount:31;
+    int m_childCount;//:31;
     bool m_populated:1;
 };
 
@@ -703,6 +703,7 @@
             else {
                 KDirModelDirNode* dirNode = static_cast<KDirModelDirNode *>(node);
                 int count = dirNode->childCount();
+// here count == 2147483647 and ChildCountUnknown == -1 on Solaris, initially -> never true
                 if (count == ChildCountUnknown && item.isReadable()) {
                     const QString path = item.localPath();
                     if (!path.isEmpty()) {
@@ -743,7 +744,7 @@
                             ::closedir(dir);
                         }
 #endif
-                        //kDebug(7008) << "child count for " << path << ":" << count;
+                        kDebug(7008) << "child count for " << path << ":" << count;
                         dirNode->setChildCount(count);
                     }
                 }
------------------------------------>8---

Reproducible: Always

Steps to Reproduce:
Run dolphin on Solaris and select 'Details' view.

Actual Results:  
The 'Size' column of 'Details' view reports "2,147,483,647 items" with all listed directories.

Expected Results:  
The 'Size' column will report correct number of entries for each subdirectory.