I think "Calendar" Module some issues with displaying correct dates..

I am experiencing the same issue with a 5.x-1.2 install. 3/1/2007 events do not appear in the month view (in my case they do appear in the week view.

$content[type] = array (
'name' => 'Event',
'type' => 'event',
'description' => 'An event, meeting, or appointment.',
'title_label' => 'Title',
'body_label' => 'Body',
'min_word_count' => '0',
'help' => '',
'node_options' =>
array (
'status' => true,
'revision' => true,
'promote' => false,
'sticky' => false,
),
'comment' => '2',
'upload' => '1',
'old_type' => 'event',
'orig_type' => '',
'module' => 'node',
'custom' => '1',
'modified' => '1',
'locked' => '0',
);
$content[fields] = array (
0 =>
array (
'widget_type' => 'options_buttons',
'label' => 'Requirements',
'weight' => '0',
'description' => 'Check boxes for any special requirements for this event.',
'group' => false,
'required' => '0',
'multiple' => '1',
'text_processing' => '0',
'max_length' => '',
'allowed_values' => 'Laptop Lab
Marratech
Polycom
Food (details in description)
Other (details in description)',
'allowed_values_php' => '',
'field_name' => 'field_tech_requirements',
'field_type' => 'text',
'module' => 'text, optionwidgets',
),
1 =>
array (
'widget_type' => 'options_select',
'label' => 'Room',
'weight' => '0',
'description' => '',
'group' => false,
'required' => '0',
'multiple' => '0',
'text_processing' => '0',
'max_length' => '',
'allowed_values' => 'Hobbs
White
Auditorium
Heim
Upstairs
Pratt
Great Bend
',
'allowed_values_php' => '',
'field_name' => 'field_room',
'field_type' => 'text',
'module' => 'text, optionwidgets',
),
2 =>
array (
'widget_type' => 'date_select',
'label' => 'Start',
'weight' => '0',
'select_day' => '1',
'select_month' => '1',
'select_year' => '1',
'years_back' => '3',
'years_forward' => '3',
'increment' => '1',
'description' => '',
'group' => false,
'required' => '1',
'multiple' => '1',
'granularity' =>
array (
'Y' => 'Y',
'M' => 'M',
'D' => 'D',
'H' => 'H',
'N' => 'N',
),
'todate' => 'optional',
'input_format' => 'site-wide',
'input_format_custom' => '',
'output_format_date' => 'm/d/Y - g:ia',
'output_format_zone' => '',
'output_format_custom' => '',
'output_format_date_long' => 'l, F j, Y - g:ia',
'output_format_zone_long' => '',
'output_format_custom_long' => '',
'output_format_date_medium' => 'D, m/d/Y - g:ia',
'output_format_zone_medium' => '',
'output_format_custom_medium' => '',
'output_format_date_short' => 'm/d/Y - g:ia',
'output_format_zone_short' => '',
'output_format_custom_short' => '',
'tz_handling' => 'site',
'field_timezone' => 'America/Chicago',
'field_name' => 'field_start',
'field_type' => 'date',
'module' => 'date',
),
);

I'm experiencing the same problem. I built a form using CCK, it has a Date field in it, and
I made CaseTracker manage that type as a Case. I created a Calendar View to
show these types, and it works fine, except for Month view, when the date is
the first of the month. The Month view shows events on all other days just fine.
And week, day, and year views show the first of the month events just fine.

This is a show stopper for me. Can someone fix quickly?

I posted the same issue ias a date.module bug report
The maintainer seems to have a lot on her plate, and we (non-programmers) are doing as much as we can to help

I have a question to help narrow down the trouble. Do your installations have the same other troubles described below?

My calendar on the month view also does not show content with the date field set on the first of the month.
In addition (if I remember my days right)
On the week view it does not show content set for Tuesdays if Drupal is set for weeks beginning Monday.
On the week view it does not show content set for Tuesdays and Wednesdays if Drupal is set for weeks beginning Sunday.

Maybe we can figure out which module needs adjustment

In my case (details in my post above), I can see this:

In the week view, with the first day of the week set as Sunday, Monday's events are not visible.
In the week view, if I set the first day of the week to Monday, Mondays' events are still the only events not visible.
I don't seem to be able to set the first day of the week to days other than Sunday or Monday . . .

I have just noticed that if I select "day" to view just a given day the times I get are ALL wrong (all show the same time, 6 pm).

Found the problem, which is twofold:

1) If you create a date that has no hours granularity, it will set hours to midnight. If you set that date up to do timezone conversions, the date will get reset back or be displayed as the previous day if you live in a place where timezone conversion is negative (east of the prime meridian). Therefore, you must not use timezone conversion on dates that have no hours. I have updated the Date module to not allow that any more, but if you have date fields already created, you will need to go back into the settings and set them to do 'No timezone conversion'.

2) The calendar module needed a patch to properly handle the 'no timezone conversion' option so it didn't try to do it anyway, and that patch was just committed.

SWEET! Thanks very much, both of you!