Invalid argument supplied for foreach() in includes/common.inc

Looking for some pointers as to what might be causing the following warning messages upon enabling Views module?

I've been trying to customize an addressbook module based on someone's code available here http://www.plaatsoft.nl/wiibrew/addressbook/
In the essence, the code runs without any issues on its own. As soon as I would enable "Views" module, I get the following errors and the Views module starts acting weird... So it seems as if there is some collision happening since each module works fine on it's own.

While the addressbook module was initially developed for Drupal 5.x, I used the Deadwood module to help convert the module to 6.x platform.

Here are the warning messages I get:

    * warning: Invalid argument supplied for foreach() in /htdocs/includes/common.inc on line 3298.
    * warning: array_merge() [function.array-merge]: Argument #2 is not an array in /htdocs/includes/common.inc on line 3180.
    * warning: array_merge() [function.array-merge]: Argument #1 is not an array in /htdocs/includes/common.inc on line 3180.
    * warning: array_merge() [function.array-merge]: Argument #1 is not an array in /htdocs/includes/common.inc on line 3180.
    * warning: array_merge() [function.array-merge]: Argument #1 is not an array in /htdocs/includes/common.inc on line 3180.

warning: Invalid argument supplied for foreach() in /usr/local/apache2/htdocs/sandbox.soroki.com/includes/common.inc on line 3298.

   3287 /**
   3288  * Fill in required default values for table definitions returned by hook_schema().
   3289  *
   3290  * @param $module
   3291  *   The module for which hook_schema() was invoked.
   3292  * @param $schema
   3293  *   The schema definition array as it was returned by the module's
   3294  *   hook_schema().
   3295  */
   3296 function _drupal_initialize_schema($module, &$schema) {
   3297   // Set the name and module key for all tables.
   3298   foreach ($schema as $name => $table) {
   3299     vsm_trace();
   3300     if (empty($table['module'])) {
   3301       $schema[$name]['module'] = $module;
   3302     }
   3303     if (!isset($table['name'])) {
   3304       $schema[$name]['name'] = $name;
   3305     }
   3306   }
   3307 }

warning: array_merge() [function.array-merge]: Argument #2 is not an array in /usr/local/apache2/htdocs/sandbox.soroki.com/includes/common.inc on line 3180.

   3151 /**
   3152  * Get the schema definition of a table, or the whole database schema.
   3153  *
   3154  * The returned schema will include any modifications made by any
   3155  * module that implements hook_schema_alter().
   3156  *
   3157  * @param $table
   3158  *   The name of the table. If not given, the schema of all tables is returned.
   3159  * @param $rebuild
   3160  *   If true, the schema will be rebuilt instead of retrieved from the cache.
   3161  */
   3162 function drupal_get_schema($table = NULL, $rebuild = FALSE) {
   3163   static $schema = array();
   3164
   3165   if (empty($schema) || $rebuild) {
   3166     // Try to load the schema from cache.
   3167     if (!$rebuild && $cached = cache_get('schema')) {
   3168       $schema = $cached->data;
   3169     }
   3170     // Otherwise, rebuild the schema cache.
   3171     else {
   3172       $schema = array();
   3173       // Load the .install files to get hook_schema.
   3174       module_load_all_includes('install');
   3175
   3176       // Invoke hook_schema for all modules.
   3177       foreach (module_implements('schema') as $module) {
   3178         $current = module_invoke($module, 'schema');
   3179         _drupal_initialize_schema($module, $current);
   3180         $schema = array_merge($schema, $current);
   3181         vsm_trace();
   3182       }
   3183
   3184       drupal_alter('schema', $schema);
   3185       cache_set('schema', $schema);
   3186     }
   3187   }
   3188
   3189   if (!isset($table)) {
   3190     return $schema;
   3191   }
   3192   elseif (isset($schema[$table])) {
   3193     return $schema[$table];
   3194   }
   3195   else {
   3196     return FALSE;
   3197   }
   3198 }

Here is my setup:

Drupal core 6.13
Views 6.x-2.x-dev
PHP 5.2.9
Apache/2.2.11

If I missed any details, please let me know.

Thanks in advance!