diff --git a/bindings/java/src/org/hyperic/sigar/test/TestPTQL.java b/bindings/java/src/org/hyperic/sigar/test/TestPTQL.java
index 38cf63bc..7f504169 100644
--- a/bindings/java/src/org/hyperic/sigar/test/TestPTQL.java
+++ b/bindings/java/src/org/hyperic/sigar/test/TestPTQL.java
@@ -61,6 +61,7 @@ public class TestPTQL extends SigarTestCase {
         "Args.*.eq=org.apache.tools.ant.Main", //'*' == any arg
         "Args.*.ct=java", //'*' == any arg
         "Args.*.ew=sigar.jar", //'*' == any arg
+        "Modules.*.re=libc|kernel",
         "Port.tcp.eq=80,Cred.Uid.eq=0", //root owned http port
         "Port.udp.eq=161,Cred.Uid.eq=0", //root owned snmp port
         "Port.tcp.eq=8080,Cred.Uid.eq=1003", //dougm owned jboss port
diff --git a/src/os/darwin/darwin_sigar.c b/src/os/darwin/darwin_sigar.c
index b32e726b..d18f317c 100644
--- a/src/os/darwin/darwin_sigar.c
+++ b/src/os/darwin/darwin_sigar.c
@@ -39,6 +39,7 @@
 #include <mach/thread_info.h>
 #include <mach/vm_map.h>
 #include <mach/shared_memory_server.h>
+#include <mach-o/dyld.h>
 #define __OPENTRANSPORTPROVIDERS__
 #include <Gestalt.h>
 #include <CFString.h>
@@ -460,7 +461,8 @@ int sigar_mem_get(sigar_t *sigar, sigar_mem_t *mem)
         return status;
     }
 
-    mem->free = vmstat.free_count * sigar->pagesize;
+    mem->free = vmstat.free_count;
+    mem->free *= sigar->pagesize;
 #elif defined(__FreeBSD__)
     if ((status = sigar_vmstat(sigar, &vmstat)) == SIGAR_OK) {
         mem->free = vmstat.v_free_count;
@@ -1884,10 +1886,36 @@ int sigar_proc_exe_get(sigar_t *sigar, sigar_pid_t pid,
 #endif
 }
 
+#ifdef DARWIN
+static int sigar_dlinfo_modules(sigar_t *sigar, sigar_proc_modules_t *procmods)
+{
+    uint32_t i, count = _dyld_image_count();
+
+    for (i=0; i<count; i++) {
+        int status;
+        const char *name =
+            _dyld_get_image_name(i);
+
+        if (name == NULL) {
+            continue;
+        }
+        status =
+            procmods->module_getter(procmods->data,
+                                    (char *)name, strlen(name));
+
+        if (status != SIGAR_OK) {
+            /* not an error; just stop iterating */
+            break;
+        }
+    }
+    return SIGAR_OK;
+}
+#endif /* DARWIN */
+
 int sigar_proc_modules_get(sigar_t *sigar, sigar_pid_t pid,
                            sigar_proc_modules_t *procmods)
 {
-#ifdef SIGAR_HAS_DLINFO_MODULES
+#if defined(SIGAR_HAS_DLINFO_MODULES) || defined(DARWIN)
     if (pid == sigar_pid_get(sigar)) {
         return sigar_dlinfo_modules(sigar, procmods);
     }
diff --git a/src/sigar_ptql.c b/src/sigar_ptql.c
index 834d6c11..4fc560d4 100644
--- a/src/sigar_ptql.c
+++ b/src/sigar_ptql.c
@@ -1144,6 +1144,65 @@ static int SIGAPI ptql_args_match(sigar_t *sigar,
     return matched ? SIGAR_OK : !SIGAR_OK;
 }
 
+typedef struct {
+    sigar_t *sigar;
+    ptql_branch_t *branch;
+    sigar_uint32_t ix;
+    int matched;
+} proc_modules_match_t;
+
+static int proc_modules_match(void *data, char *name, int len)
+{
+    proc_modules_match_t *matcher =
+        (proc_modules_match_t *)data;
+    ptql_branch_t *branch = matcher->branch;
+
+    if (branch->op_flags & PTQL_OP_FLAG_GLOB) { /* Modules.*.ct=libc */
+        matcher->matched =
+            ptql_str_match(matcher->sigar, branch, name);
+
+        if (matcher->matched) {
+            return !SIGAR_OK; /* stop iterating */
+        }
+    }
+    else {
+        if (matcher->ix++ == branch->data.ui32) { /* Modules.3.ct=libc */
+            matcher->matched =
+                ptql_str_match(matcher->sigar, branch, name);
+            return !SIGAR_OK; /* stop iterating */
+        }
+    }
+
+    return SIGAR_OK;
+}
+
+static int SIGAPI ptql_modules_match(sigar_t *sigar,
+                                     sigar_pid_t pid,
+                                     void *data)
+{
+    ptql_branch_t *branch =
+        (ptql_branch_t *)data;
+    int status;
+    sigar_proc_modules_t procmods;
+    proc_modules_match_t matcher;
+
+    matcher.sigar = sigar;
+    matcher.branch = branch;
+    matcher.ix = 0;
+    matcher.matched = 0;
+
+    procmods.module_getter = proc_modules_match;
+    procmods.data = &matcher;
+
+    status = sigar_proc_modules_get(sigar, pid, &procmods);
+
+    if (status != SIGAR_OK) {
+        return status;
+    }
+
+    return matcher.matched ? SIGAR_OK : !SIGAR_OK;
+}
+
 typedef struct {
     const char *key;
     int klen;
@@ -1316,6 +1375,10 @@ static ptql_lookup_t PTQL_Args[] = {
     { NULL, ptql_args_match, 0, 0, PTQL_VALUE_TYPE_ANY, ptql_args_branch_init }
 };
 
+static ptql_lookup_t PTQL_Modules[] = {
+    { NULL, ptql_modules_match, 0, 0, PTQL_VALUE_TYPE_ANY, ptql_args_branch_init }
+};
+
 static ptql_lookup_t PTQL_Env[] = {
     { NULL, ptql_env_match, 0, 0, PTQL_VALUE_TYPE_ANY, ptql_branch_init_any }
 };
@@ -1342,6 +1405,7 @@ static ptql_entry_t ptql_map[] = {
     { "State",    PTQL_State },
     { "Fd",       PTQL_Fd },
     { "Args",     PTQL_Args },
+    { "Modules",  PTQL_Modules },
     { "Env",      PTQL_Env },
     { "Port",     PTQL_Port },
     { "Pid",      PTQL_Pid },